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Purpose: Left bundle branch area pacing (LBBAP) has emerged as a physiological and stable form of pacing. We aim to compare the mechanical ventricular synchrony of LBBP, LBFP, and LVSP. Methods: Proximal Left bundle branch pacing (LBBP), left bundle fascicular pacing (LBFP) and left ventricular septal pacing (LVSP) were identified in patients with bradycardia who successfully underwent LBBAP. Patients with left ventricular ejection fraction (LVEF) < 50% or QRS duration (QRSd) ≥ 120 ms were excluded. By using electrocardiograms, the left ventricular activation time (LVAT) and QRS duration (QRSd) were measured to examine electrophysiological synchrony. As indications of mechanical synchrony, global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS), and peak strain dispersion (PSD) were evaluated by using 2-dimensional speckle tracking echocardiography (2D-STE). Results: In 56 patients, data were collected during LBBP (n = 18), LBFP (n = 16), and LVSP (n = 22). LVSP resulted in a longer LVAT (91.3 ± 14.9 ms) than LBBP (77.1 ± 10.8 ms, P < 0.05) and LBFP (72.1 ± 9.6 ms, P < 0.05), but all three groups had similar QRSd. There were no differences in GLS, GCS, GRS, or PSD between LBBP, LBFP, and LVSP. Conclusions: In patients with normal cardiac function and narrow QRS, though LBBAP with LBB capture resulted in better electrophysiological synchrony than without, the mechanical synchrony of the three groups was comparable. [ABSTRACT FROM AUTHOR]

Landslides represent significant risks to human activity, leading to infrastructure damage and loss of life. This study focuses on assessing landslide hazards in Utmah Region, Yemen. The evaluation involves comparing the effectiveness of the relative frequency ratio model with five machine learning algorithms (MLAs) for hazard mapping. Field surveys, high-resolution satellite imagery, and aerial photography were utilized in the study. The inventory map was generated after identifying and mapping 100 landslides. The inventory was then divided randomly into a training dataset (70 landslides) and a validation dataset (30 landslides), with an equal number of non-landslide pixels. Eleven additional landslide conditioning factors were collected from various sources, and the frequency ratio (FR) approach was employed to identify the most crucial variables for modeling. The models were rigorously tested and assessed using statistical metrics, including the Friedman and Wilcoxon signed-rank tests, as well as the area under the receiver operating characteristics (AUROC) curve. The findings based on the training and validation datasets revealed that the RF algorithm (AUROC, 0.992) outperformed the other models in generating hazard maps. The XGBoost model (AUROC, 0.991), NB model (AUROC, 0.970), ANN model (AUROC, 0.922), KNN model (AUROC, 0.877), and FR (AUROC, 0.674) were found to be less effective. Consequently, the study highlights that the Random forest (RF) model shows promise as an effective approach for predicting landslides spatially on a global scale. [ABSTRACT FROM AUTHOR]

Background: To evaluate the feasibility of using radiolabeled fibroblast activation protein inhibitor (FAPI) PET/CT imaging to assess activated fibroblasts in the atria of individuals with AF and to identify factors contributing to enhanced atrial activity. Methods: We constructed left atrial appendage (LAA) pacing beagle dog AF models (n = 5) and conducted 18F-FAPI PET/CT imaging at baseline and eight weeks after pacing. Right atrial (RA) specimens were collected from these models. Additionally, 28 AF patients and ten age- and sex-matched healthy volunteers underwent 18F-FAPI PET/CT imaging. Results: RA of AF beagles showed increased 18F-FAPI uptake. Among AF patients, 18 out of 28 (64.3%) exhibited enhanced atrial FAPI activity. No atrial 18F-FAPI uptake was observed in the sham beagle and healthy volunteers. In animal RA specimens, 18F-FAPI activity correlated positively with FAP mRNA (r =.98, P =.002) and protein (r =.82, P =.03) levels, as well as collagen I mRNA expression (r =.85, P =.02). B-type natriuretic peptide levels were associated with atrial 18F-FAPI activity (OR = 3.01, P =.046). Conclusion: This proof-of-concept study suggests that 18F-FAPI PET/CT imaging may be a feasible method for evaluating activated fibroblasts in the atria of AF patients. [ABSTRACT FROM AUTHOR]

Earth fissures are potential hazards that often cause severe damage and affect infrastructure, the environment, and socio-economic development. Owing to the complexity of the causes of earth fissures, the prediction of earth fissures remains a challenging task. In this study, we assess earth fissure hazard susceptibility mapping through four advanced machine learning algorithms, namely random forest (RF), extreme gradient boosting (XGBoost), Naïve Bayes (NB), and K-nearest neighbor (KNN). Using Qa' Jahran Basin in Yemen as a case study area, 152 fissure locations were recorded via a field survey for the creation of an earth fissure inventory and 11 earth fissure conditioning factors, comprising of topographical, hydrological, geological, and environmental factors, were obtained from various data sources. The outputs of the models were compared and analyzed using statistical indices such as the confusion matrix, overall accuracy, and area under the receiver operating characteristics (AUROC) curve. The obtained results revealed that the RF algorithm, with an overall accuracy of 95.65% and AUROC, 0.99 showed excellent performance for generating hazard maps, followed by XGBoost, with an overall accuracy of 92.39% and AUROC of 0.98, the NB model, with overall accuracy, 88.43% and AUROC, 0.96, and KNN model with general accuracy, 80.43% and AUROC, 0.88), respectively. Such findings can assist land management planners, local authorities, and decision-makers in managing the present and future earth fissures to protect society and the ecosystem and implement suitable protection measures. [ABSTRACT FROM AUTHOR]

The instability of TiN/HfZrO/TiN ferroelectric capacitors becomes a dominant obstacle in its practical application. To improve this problem, the effects of N-plasma treatment at both top and bottom TiN interfaces are investigated on the ferroelectricity behaviors and reliability characteristics of TiN/HfZrO/TiN ferroelectric capacitors. The results show that the high remanent polarization and large dielectric constant in the capacitors can be obtained by treating at the both top and bottom TiN interfaces. The wake-up and fatigue effects can be effectively suppressed and the lower leakage current can be acquired with extending the treatment time. The XPS analyses show that the oxygen vacancies in HfZrO film can be reduced efficiently by extending treatment time. The cycling test confirms that the better ferroelectricity characteristics can be measured by treating at two interfaces than that of single interface. The N-plasma treatment at both top and bottom TiN interfaces provides a new approach for the realization of highly reliable TiN/HfZrO/TiN ferroelectric capacitors. [ABSTRACT FROM AUTHOR]

In this article, we discuss a straightforward method of parameter extraction, which was used in two back-to-back connected Schottky diodes previously. We verified the universality and feasibility of this method by extracting the solar cell parameters from J to V curves. This method provides a flexible approach to extract parameters of some complex models that are impracticable using other methods. In addition, we discussed the authenticity problem for parameter extraction and its widely used solution, deforming the formula by using some approximation to make the object parameter the slope or intercept. We argued that it is necessary to analyze how the error transformed into the deductive curve, which is generally overlooked. Moreover, we illustrated the defect of the ordinary least squares method under the absolute least squares criterion. Under some conditions, such as when the point under larger coordinates has a larger error, it is more accurate to use the least squares method under the relative least-squares criterion. [ABSTRACT FROM AUTHOR]

Global warming has increased the prevalence and severity of natural disasters, such as the increased frequency and intensity of drought events. In this study, we employed the standardized precipitation evapotranspiration index (SPEI) and standardized precipitation index (SPI) to analyze and predict the temporal and spatial variation of drought and its characteristics in the Songliao Plain under two global warming scenarios (1.5 and 2 °C). We used climate model data provided by the Inter-Sectoral Impact Model Intercomparison Project. The results show that drought will become more frequent in the future; it is more serious at representative concentration pathway (RCP) 8.5 than RCP4.5 and under global warming of 1.5 °C than 2 °C. Geographically, the SPEI indicates that there are signs of drought in the northwest and northeast of Songliao Plain while the SPI indicates that drought decreases from north to south. In terms of drought characteristics, the drought barycenter expressed by the SPEI moves to the northeast, while the drought barycenter expressed by the SPI moves to the northwest. The SPI relies on a single meteorological factor, making the SPI mutation test more stable. Finally, compared to the historical period (1976–2005), the frequency and duration of drought have increased, and it is more reliable to use the SPEI to monitor drought in this area. [ABSTRACT FROM AUTHOR]

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Background: Thoracoscopic ablation has emerged as an effective therapy for patients with long-standing persistent Atrial fibrillation (LsPAF). We aimed to investigate the immediate electrophysiological characteristics following modified ablation with 3 circular and 3 linear lesions in the thoracoscopic procedure via a unilateral approach. Methods: Between May 2015 and October 2018, 40 patients underwent the one-stage hybrid procedure for LsPAF. Isolation of the pulmonary veins (PV) and left atrium posterior wall (LAPW), excision of the left atrial appendage (LAA), and high-density endocardial mapping and individualized percutaneous catheter ablation for AF termination were performed. Results: The modified thoracoscopic procedure may enable successful PV and LAPW isolation and LAA removal. Endocardial electrophysiological examination showed 6 out of 40 (15%) patients with a right PV gap, 3 (7.5%) patients with incomplete roof lesions, and 8 (20%) patients with incomplete Dallas lesions. A total of 44 driving areas were mapped and ablated. Thirty-five patients achieved procedural AF termination. After a mean follow-up period of 26 months, the success rate of a single procedure was 85%. Cox regression analysis demonstrated that the failure of procedural AF termination may be a risk factor in atrial tachyarrhythmia recurrence. Discussion: Endocardial electrophysiological examination is a necessary partner to thoracoscopic ablation. Our modified thoracoscopic ablation and driving areas-based ablation contribute to high rates of procedural AF termination, which may lead to reduced recurrence rate. The hybrid procedure may be an effective strategy for the management of LsPAF. [ABSTRACT FROM AUTHOR]

Background: Pulmonary vein isolation (PVI) has become the cornerstone of atrial fibrillation (AF) ablation, but long-term success rates remains suboptimal, due in large part to late PV reconnection and insufficient ostial substrate modification.Objective: To evaluate whether ablation index (AI)-guided PVI with electrical isolation and quantified ostial substrate modification improves clinical outcomes when compared with contact force (CF)-guided ablation in patients with paroxysmal atrial fibrillation (PAF).Methods: The PAF-AI trial (ChiCTR1900022041) is a prospective, multi-center, randomized controlled clinical trial enrolling patients with PAF with an indication for catheter ablation. Patients are randomized into a 2:1 fashion to two treatment arms: AI-guided PVI (n = 151) and CF-guided PVI (n = 75). In the AI-guided PVI group, real-time automated display of radiofrequency applications (Visitag™) is used with AI ≥ 500 recommended at the anterior/superior/inferior walls and 350-400 at the posterior wall. In CF-guided PVI group, the value and direction of CF are displayed, with the lesion dots manually annotated. The primary endpoint is the freedom from AF recurrence at 12 months following ablation, without antiarrhythmic drug. The primary pre-specified secondary endpoints include intraprocedural efficiency and peri-procedural complications.Conclusions: PAF-AI trial compares the effectiveness and safety of two different strategies of PVI in patients with PAF, AI-guided PVI versus more established CF-guided PVI. This prospective, multi-center, randomized controlled trial, with comparative data evaluating procedural and long-term follow-up results, aims to evaluate the impact of AI-guided strategy on AF ablation compared with the current standard of care RF ablation approach. [ABSTRACT FROM AUTHOR]

As a major agricultural province in China, it is necessary to study the content of heavy metals in farmland soil and crop in Jilin Province and to evaluate the risks to ecology and human health. This study presented the work completed on 79 soil samples, 10 rice samples, 66 maize samples and 15 soybean samples collected from Jilin Province farmland and evaluated six heavy metals (Zn, Cu, Pb, Cd, Hg and As) concentrations. The results showed that the concentrations of the six heavy metals in farmland soil and crop samples from Jilin Province basically met the soil standards and food health standards of China. The agricultural soil pollution spatial distribution was the most serious in the south of Jilin Province and the lightest in the west. The non-carcinogenic risks faced by children eating crops were higher than those of adults, but the carcinogenic risks were lower than those of adults. Both of the two health risks to adults and children from eating crops were very limited. The results would help determine the heavy metals pollution in farmland soil in Jilin Province efficiently and accurately and helped decision makers to achieve a balance between production and environmental regulation. [ABSTRACT FROM AUTHOR]

Background: This retrospective study was designed to explore the factors relevant to increased atrial 18F-fluorodeoxyglucose (FDG) uptake in patients with atrial fibrillation (AF) who had undergone routine whole-body positron emission tomography/computed tomography (PET/CT) imaging. Methods and Results: Forty-eight consecutive AF patients (32 persistent, 16 paroxysmal) were identified from our routine FDG PET/CT database. Twenty-two control subjects were selected to establish the normal range of FDG uptake (maximum standardized uptake value, SUVmax) in target tissues. A target-to-background ratio (TBR) was calculated to determine abnormal uptake in the atrium and atrial appendage (AA). Univariate comparisons and multivariate regression analyses were conducted to explore the factors associated with the increased FDG accumulation in the atrium and AA. Seventeen AF patients, all with persistent AF, had increased atrial FDG uptake. Most of them (14, or 82.4%) had increased uptake in the right atrium. Eleven AF patients, 9 with persistent AF, had increased uptake in the AA, and bilateral AAs were equally involved. Multivariate logistic regression analyses identified that female gender, persistent AF, and activity in epicardial adipose tissue (EAT) were independent factors predicting the increased activity of the atrium; also, SUVmax of the left ventricle was found for the AA. In addition, multivariate linear regression analyses showed that EAT activity was the only independent variable linearly correlated with the activity of the atrium and AA. Conclusions: Atrial uptake was present in persistent AF and localized mainly in the right atrium, whereas bilateral AAs could be equally involved. Multiple factors contributed to the increased activity in atrium; in particular, the EAT activity was independently correlated with the activity of the atrium and AA. [ABSTRACT FROM AUTHOR]

The flexible unipolar resistive switching characteristics of Au/Ni/HZO/Au devices on Polyethylene terephthalate substrates have been investigated for the RRAM applications. The devices demonstrated a bistable and reproducible unipolar RS behavior with a high OFF/ON ratio about 10, and the memory widow could be maintained in repetitive programming/erase at least 1000 cycles. The retention property has no degradation at 6.3 × 10 seconds. The current-voltage characteristics of the HZO samples show that the Ohmic contact and space charge limited current are suggested to response for the low resistance state and high resistance state, respectively. Combined with the conductance mechanism, the resistive switching behaviors can be explained by the conductive filaments model. The RS mechanism is attributed to restore and rupture caused by the joule heating and the redox reaction induced by the external electron injection. The memory devices also show good mechanical flexibility. It is believed that the HZO-based memory device has great potential to be used in high performance, flexible memory applications. [ABSTRACT FROM AUTHOR]

Lead hafnate titanate (PHT) thin film was deposited by pulse laser deposition, characterized for the usage as a ferroelectric capacitor in view of Ferroelectric Random Access Memory (FeRAM) devices, and compared with a lead zirconate titanate (PZT) reference, which was fabricated in the same conditions. Results indicate that the 126 nm-thickness PHT thin film with a low temperature self-buffer layer has a single (111)-orientation. The following electric measurements were performed to investigate the possibility of this thin film to use in the FeRAM applications by contrast to a PZT reference. This PHT sample demonstrates a good ferroelectric property with the remanent polarization of 51 μC/cm. The remanent polarization with no obvious degradation has been observed after 2 × 10 fatigue reversals, which indicate that the PHT thin film a promising candidate in view of FeRAM applications. [ABSTRACT FROM AUTHOR]

Grassland fire disaster is one of the most destructive grassland disasters, which is sudden, destructive, and hard to handle. It caused a great threat to the humanity and property in pastoral. In this study, a dynamic risk assessment model was built based on the data of prairie fire statistics and related meteorological data from 1994 to 2005 in the six livestock counties of Hulunbuir grassland. Logistic regression model was used in the identification of the key factors influence grassland fire disaster risk. In the calculation of the weight of individual indicators, analytic hierarchy through scoring by experts was used. Grid GIS technology combined with regression analysis was used in the spatial distribution of indicators which has higher resolution than counties. Assessment factors of endogenous and exogenous sources of warning signs of grassland fires were analyzed through weighted comprehensive analysis. Fire disasters from 1994 to 2004 were taken as the sample cases to determine the threshold of risk level by using optimal partition method. Taking the grassland fires in 2005 as examples to validate the dynamic risk assessment model, results shown high risk areas coincide well with the distribution of fire points, this proved the accuracy of the model. The dynamic risk assessment results could be used to guide and manage the mitigation of grassland fire disaster and rescue goods distribution. [ABSTRACT FROM AUTHOR]

The traditional studies on drought disaster risk were based on the ground point data, which were unable to realize the continuity of space and the timeliness. It is shown that the monitoring and evaluation precision on drought were reduced significantly. However, remote sensing data in adequate spatial and temporal resolution can overcome these limitations. It can better monitor the crop in large area dynamically. This study presents a methodology for dynamic risk analysis and assessment of drought disaster to maize production in the northwest of Liaoning Province based on remote sensing data and GIS from the viewpoints of climatology, geography and disaster science. The model of dynamic risk assessment of drought disaster was established based on risk formation theory of natural disaster, and the expression of risk by integrating data came from sky, ground and space. The risk indexes were divided into four classes by data mining method, and the grade maps of drought disaster risk were drawn by GIS. It is shown that the spatial and temporal risk distributions of maize at each growth stage changed over time. The model has been verified against reduction in maize yield caused by drought. It demonstrated the reasonability, feasibility and reliability of the model and the methodology. The dynamic risk assessment of regional drought disaster for maize can be used as a tool, which can timely monitor the status (the possibility and extent of drought) and trends of regional drought disaster. The results obtained in this study can provide the latest information of regional drought disaster and the decision-making basis of disaster prevention and mitigation for government management and farmers. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) is the most common cardiac arrhythmia, and is responsible for the highest number of rhythm-related disorders and cardioembolic strokes worldwide. Early management of this condition will lower the risk of AF-associated morbidity and mortality. Targeted drug therapy has an important role in preventing the progression of AF through modification of the substrate. Discovery of the role of pulmonary veins as a trigger has been an important breakthrough, leading to the development of pulmonary vein ablation-an established curative therapy for drug-resistant AF. Identifying the underlying reasons for the abnormal firing of venous cardiomyocytes and the widespread progressive alterations of atrial tissue found in persistent AF are challenges for the future. Novel imaging techniques may help to determine the right time for intervention, provide specific targets for ablation, and judge the efficacy of treatment. If new developments can successfully address these issues, the knowledge acquired as a result will have a vital role in preclinical and early management of AF. [ABSTRACT FROM AUTHOR]