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(1) Background: the indications for transcatheter closure of large patent ductus arteriosus (PDA) with severe pulmonary hypertension (PH) are still unclear, and scholars have not fully elucidated the factors that affect PH prognosis. (2) Methods: we retrospectively enrolled 134 consecutive patients with a PDA diameter ≥10 mm or a ratio of PDA and aortic >0.5. We collected clinical data to explore the factors affecting follow-up PH. (3) Results: 134 patients (mean age 35.04 ± 10.23 years; 98 women) successfully underwent a transcatheter closure, and all patients had a mean pulmonary artery pressure (mPAP) >50 mmHg. Five procedures were deemed to have failed because their mPAP did not decrease, and the patients experienced uncomfortable symptoms after the trial occlusion. The average occluder (pulmonary end) size was almost twice the PDA diameter (22.33 ± 4.81 mm vs. 11.69 ± 2.18 mm). Left ventricular end-diastolic dimension (LVEDD), mPAP, and left ventricular ejection fraction (LVEF) significantly reduced after the occlusion, and LVEF recovered during the follow-up period. In total, 42 of the 78 patients with total pulmonary resistance >4 Wood Units experienced clinical outcomes, and all of them had PH in the follow-up, while 10 of them had heart failure, and 4 were hospitalized again because of PH. The results of a logistic regression analysis revealed that the postoperative mPAP had an independent risk factor (odds ratio = 1.069, 95% confidence interval: 1.003 to 1.140, p = 0.040) with a receiver operating characteristic curve cut-off value of 35.5 mmHg (p < 0.001). (4) Conclusions: performing a transcatheter closure of large patent ductus arteriosus is feasible, and postoperative mPAP was a risk factor that affected the follow-up PH. Patients with a postoperative mPAP >35.5 mmHg should be considered for targeted medical therapy or should undergo right heart catheterization again after the occlusion.

In this work CaO-based catalysts were found to be efficient heterogeneous catalysts for the methylation of phenol with dimethyl carbonate (DMC) in a closed high pressure reactor. The optimization experiments have been carried out to obtain best phenol conversion and the results showed that CaO catalyst modified with KCl had the best catalytic performance. When the reaction was carried out at 200°C, with phenol to dimethyl carbonate molar ratio of 1 : 2, 15% KCl/CaO catalyst dosage of 3%, reaction time 9 h, 100% conversion of phenol and 95% selectivity towards anisole have been achieved. The structure and properties of the materials were thoroughly characterized by Fourier transform infrared spectrometry (FTIR), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET). The close correlation was found between surface basicity of the catalysts and their catalytic performance for phenol conversion and anisole selectivity.

In this paper, we propose an effective neural network algorithm to perform singular value decomposition (SVD) of a cross-correlation matrix between two data streams. Different from traditional algorithms, the newly proposed algorithm can extract not only the principal singular vectors but also the corresponding principal singular values. First, a dynamical system is obtained from the gradient flow, which is obtained from optimization of a novel information criterion. Then, based on the dynamical system, a stable neural network algorithm, which can extract the left and right principal singular vectors, is obtained. Moreover, by satisfying orthogonality instead of orthonormality, we are able to extract the normalization scale factor as the corresponding singular value. In this case, the principal singular triplet (principal singular vectors and the corresponding singular value) of the cross-correlation matrix can be extracted by using the proposed algorithm. What’s more, the proposed algorithm can also be used for multiple PSTs extraction on the basis of sequential method. Then, convergence analysis shows that the proposed algorithm converges to the stable equilibrium point with probability 1. Last, experiment results show that the proposed algorithm is fast and stable in convergence, and can also extract multiple PSTs efficiently.

In this article, a CaO-based catalyst was prepared by impregnating potassium salt on CaO to develop a highly efficient heterogeneous catalyst for highly selective synthesis of anisole (AN) from phenol and dimethyl carbonate by a O-methylation. KF/CaO catalysts are highly active and selective towards formation of anisole via methylation of phenol with the highest yield of 97.48% AN was obtained at 200°C. Various reaction parameters including KF loading, the amount of catalyst and the calcination temperature on the catalytic activity were investigated. Scanning electron microscopy (SEM), X-ray diffraction (XRD), BET, CO2‑TPD and thermogravimetric (TG) were used to characterize the prepared catalyst. It was found that the high catalytic activity of CaO after modification with KF is associated with the structural aspects and the amount of basicity of the catalyst. Temperature programmed desorption of CO2 and XRD studies revealed the K2O species, a strong basic site formed by the substitution of the Ca2+ in CaO lattice by K+, might have great contribution for the high conversion of phenol and good selectivity of anisole.

Rationale: Urinary TIMP-2 (tissue inhibitor of metalloproteinases-2) and IGFBP7 (insulin-like growth factor–binding protein 7) can predict acute kidney injury (AKI) in patients with sepsis.Objectiv...

To seek for efficient Fenton-like oxidation processing for treatment of waste fracturing fluid containing hydroxypropyl guar gum (HPGG), in heterogeneous reaction, five bentonite-supported zero-valent metal catalysts were prepared by liquid-phase reduction. The results showed that the bentonite-supported zero-valent copper exhibited best catalytic performance, attributed to the high dispersion of active sites of zero-valent copper. The effects of the most relevant operating factors (H2O2 concentration, catalyst dosage, temperature and pH) were evaluated in detail. Moreover, the chemical oxygen demand removal rate of HPGG can achieve 76% when the reaction time was selected at 45 min under optimal experimental conditions. The stability evaluation showed that the catalytic performance was almost unaffected after the catalyst was recycled and used once more showing the good stability of the bentonite-supported zero-valent copper in the application process.

Steel bar corrosion inhibitor can be incorporated into concrete (or mortar) with a small amount, or coated on the cement surface to protect the steel materials. It can prevent or delay the corrosion of metal bars by directly acting on the steel bars in concrete (or mortar), but it does not affect the structure and properties of concrete. In this paper, the single component corrosion inhibitor was screened and evaluated at room temperature by salt water immersion test and static coupon weight loss method. The results show that hydrazine hydrate and KNO3 can effectively prevent the corrosion of reinforcement after being placed in simulated corrosion solution for 7 days. When the concentration of hydrazine hydrate and KNO3 is greater than 0.5%, the corrosion inhibition rate of KNO3 is 95.44% (100mg·L−1).

Transcatheter closure of inferior sinus venosus defect (ISVD) is still contraindication. To explore whether transcatheter closure with patent ductus arteriosus (PDA) occluders is possible for ISVD.From June 2014 to March 2021, 12 patients were recruited diagnosed as25 mm ISVD. The three-dimensional printing (3DP) heart model was produced based on multi-slice computed tomography (MSCT) scans. Preoperative closure simulation was planned on the personalized 3D model for each patient. Follow-up including electrocardiography (ECG), transthoracic echocardiography (TTE), and X-ray was traced.3DP models of 12 patients were successfully printed. Twelve patients had been diagnosed with25 mm ISVD and 4 of them had another secundum atrial septal defect (ASD). All patients were produced interventional therapy successfully. PDA occluder was implanted to closed ISVD, and ASD was closed using ASD occluder simultaneously. The average diameter of ISVD measured by TTE was (12.67±3.80), and the average diameter of sagittal axes and longitudinal axes measured by the 3D-printed model was (17.08±3.20) and (18.42±4.62) mm, respectively. The average size of PDA (diameter of pulmonary artery side) was (28.17±3.35) mm. Compared with the preoperative, the X-ray cardiothoracic ratio (0.51±0.04Assisting by 3D heart model, transcatheter closure of ISVD with PDA occluder had an excellent outcome. This method provides a new considerable treatment strategy for ISVD.

With both thermal insulation and load-bearing capabilities, integrated thermal protection systems (ITPS) can effectively improve structural efficiency, and thus are promising TPS concepts for future hypersonic vehicles. However, the connection structure of ITPS must adhere to the constraints of both low thermal conductivity and high mechanical performance. The layout design of the connection structure is key to successful applications of ITPS. Based on the principle of minimum net heat transfer rate and minimum strain energy, a topological optimisation method for ITPS was established to reduce both equivalent conductivity and maintain structural stiffness. Volume constraints were considered to maintain structural efficiency. ITPS designs were reconstructed from the optimised layout, and corresponding thermo-mechanical analyses were carried out. Compared to the initial design, optimised ITPSs indicate lower values in maximum back temperature, maximum deformation, and maximum component stresses. Topological optimisation method can provide a good balance between thermal insulation and load-bearing constraints in ITPS designs. With additive manufacturing technologies, these designs show promising applications.

In industrial processes, the quality of the product is crucial. The batch partial least squares (PLS) monitoring model can effectively monitor for quality-related faults. In process monitoring, to overcome time-varying disturbances, the monitoring model needs to be updated regularly. Efficiently updating the monitoring model represents a serious problem. This paper proposes a recursive concurrent projection to latent structures (RCPLS) algorithm, which can both update models more efficiently with historical model parameters and new data and provide better quality-related fault monitoring results than can static concurrent projection to latent structures (CPLS). Based on RCPLS, a complete set of process monitoring technologies is proposed. These technologies can automatically filter and store modellable data and adaptively update the online monitoring model. The updated computational quantities of the RCPLS model and the CPLS model are compared through the Tennessee Eastman process (TEP). The effectiveness of the RCPLS algorithm is verified, and a comprehensive comparison of the quality-related fault detection capabilities of RCPLS and CPLS is performed. The results show that RCPLS can significantly reduce the computational burden and increase the monitoring performance.

Detection of prognostic factors associated with patients’ survival outcome helps gain insights into a disease and guide treatment decisions. The rapid advancement of high-throughput technologies has yielded plentiful genomic biomarkers as candidate prognostic factors, but most are of limited use in clinical application. As the price of the technology drops over time, many genomic studies are conducted to explore a common scientific question in different cohorts to identify more reproducible and credible biomarkers. However, new challenges arise from heterogeneity in study populations and designs when jointly analyzing the multiple studies. For example, patients from different cohorts show different demographic characteristics and risk profiles. Existing high-dimensional variable selection methods for survival analysis, however, are restricted to single study analysis. We propose a novel Cox model based two-stage variable selection method called “Cox-TOTEM” to detect survival-associated biomarkers common in multiple genomic studies. Simulations showed our method greatly improved the sensitivity of variable selection as compared to the separate applications of existing methods to each study, especially when the signals are weak or when the studies are heterogeneous. An application of our method to TCGA transcriptomic data identified essential survival associated genes related to the common disease mechanism of five Pan-Gynecologic cancers.

Objective Obesity has been strongly linked to endometrial cancer (EC) risk. A number of potential EC risk biomarkers have been proposed, including heightened pro-inflammatory cytokines and adipokines. To evaluate if bariatric surgery can serve as a means for altering levels of such EC risk biomarkers, we investigated changes in these biomarkers after weight loss. Methods Blood samples were collected pre-operatively and 6months post-operatively in 107 female bariatric surgery patients aged 18–72years. Wilcoxon signed-rank tests were used to compare biomarker levels (measured using xMAP immunoassays) pre- and post-surgery. Normative comparisons were implemented to contrast 6-month post-surgery biomarker levels to levels in a sample of 74 age-matched non-obese women. Linear regression was used to evaluate the relationship between biomarker expression at baseline and 6months post-surgery and the relationship between race and biomarker levels. Results On average, participants lost 30.15kg (SD: 12.26) after the bariatric intervention. Levels of C-peptide, insulin, CRP, leptin, IL-1Rα, and IL-6 significantly decreased, while levels of SHBG, IGFBP1, and adiponectin significantly increased with weight loss. Normative comparisons showed the levels of SHBG, C-peptide, insulin, IGFBP1, adiponectin, CRP, and TNFα after bariatric intervention approached the level of markers in comparison group. Multiple regression analyses revealed significant relationships between changes in BMI and changes in biomarker levels. The changes in IL-1Rα were significantly associated with race. Conclusions Our findings demonstrate that normalization of EC risk biomarkers can be achieved with bariatric surgery. Improved understanding of biological mechanisms associated with weight loss may inform preventive strategies for EC.

In this paper, a effective algorithm to effectively estimate the singular component and value from the cross-covariance kind of matrix from two data streams by using the neural network approach. Different from traditional algorithms, the newly proposed algorithm can estimate not only the principal singular vectors (PSVRs) but also the principal singular values (PSVEs). First, a dynamical system is obtained from the gradient flow, which is obtained from the optimization of a novel information criterion. Then, based on the dynamical system, a stable neural network algorithm, which can extract the left and right PSVRs, is obtained. Moreover, the PSVE can also be obtained based on the estimated left or (and) right singular vectors (SVRs), because the norm of the SVRs mainly depends on the corresponding singular value (SVE) of the cross-covariance matrix. In this case, the principal singular triplet (PST, PSVRs and the corresponding SVE) of the cross-covariance matrix can be extracted by using the algorithm proposed in this paper. What’s more, the algorithm proposed in this paper can also be used for multiple PSTs extractions on the basis of the sequential method. Then, the convergence of the algorithm is analyzed, and the result illustrates that the algorithm proposed in this paper converges to the stable equilibrium point with probability 1. Last, experiment results show that the algorithm proposed in this paper is fast and stable in convergence, and can also extract multiple PSTs efficiently.

Partial least square (PLS) is a multivariate statistical analysis method which can distinguish the quality-related and quality-unrelated spaces. Modification of PLS (MPLS) is an improved algorithm for PLS. However, MPLS has the disadvantages of large amount of calculation in batch modeling and cannot overcome the dynamic disturbance in process monitoring. In order to solve this problem, we propose an adapt recursive modified latent structure (AR-MPLS) algorithm, which uses recursive structure to extend to the dynamic domain. Finally, we use the Tennessee-Eastman process to verify the effectiveness of the proposed algorithm in the dynamic domain.

In the time-varying industrial process, the quality of the product is crucial. The existing batch partial least squares (PLS) monitoring model can effectively monitor quality-related faults. In process monitoring, in order to overcome time-varying disturbances, the monitoring model needs to update regularly. How to update the monitoring model efficiently is a serious problem. This paper proposes a recursive concurrent projection to latent structures (RCPLS) algorithm, which can update models more efficiently with historical model parameters and new data, and can also provide better quality-related fault monitoring results than static concurrent projection to latent structures (CPLS). The updated computational quantities of the RCPLS model and the CPLS model are compared through the Tennessee Eastman Process (TEP). The effectiveness of the RCPLS algorithm is verified, and a comprehensive comparison of the quality-related fault detection capabilities of RCPLS and CPLS is performed. The results show that RCPLS can significantly reduce the computational burden and increase monitoring effectiveness.

IMPORTANCE: Sepsis is a heterogeneous syndrome. Identification of distinct clinical phenotypes may allow more precise therapy and improve care. OBJECTIVE: To derive sepsis phenotypes from clinical data, determine their reproducibility and correlation with host-response biomarkers and clinical outcomes, and assess the potential causal relationship with results from randomized clinical trials (RCTs). DESIGN, SETTINGS, AND PARTICIPANTS: Retrospective analysis of data sets using statistical, machine learning, and simulation tools. Phenotypes were derived among 20 189 total patients (16 552 unique patients) who met Sepsis-3 criteria within 6 hours of hospital presentation at 12 Pennsylvania hospitals (2010-2012) using consensus k means clustering applied to 29 variables. Reproducibility and correlation with biological parameters and clinical outcomes were assessed in a second database (2013-2014; n = 43 086 total patients and n = 31 160 unique patients), in a prospective cohort study of sepsis due to pneumonia (n = 583), and in 3 sepsis RCTs (n = 4737). EXPOSURES: All clinical and laboratory variables in the electronic health record. MAIN OUTCOMES AND MEASURES: Derived phenotype (α, β, γ, and δ) frequency, host-response biomarkers, 28-day and 365-day mortality, and RCT simulation outputs. RESULTS: The derivation cohort included 20 189 patients with sepsis (mean age, 64 [SD, 17] years; 10 022 [50%] male; mean maximum 24-hour Sequential Organ Failure Assessment [SOFA] score, 3.9 [SD, 2.4]). The validation cohort included 43 086 patients (mean age, 67 [SD, 17] years; 21 993 [51%] male; mean maximum 24-hour SOFA score, 3.6 [SD, 2.0]). Of the 4 derived phenotypes, the α phenotype was the most common (n = 6625; 33%) and included patients with the lowest administration of a vasopressor; in the β phenotype (n = 5512; 27%), patients were older and had more chronic illness and renal dysfunction; in the γ phenotype (n = 5385; 27%), patients had more inflammation and pulmonary dysfunction; and in the δ phenotype (n = 2667; 13%), patients had more liver dysfunction and septic shock. Phenotype distributions were similar in the validation cohort. There were consistent differences in biomarker patterns by phenotype. In the derivation cohort, cumulative 28-day mortality was 287 deaths of 5691 unique patients (5%) for the α phenotype; 561 of 4420 (13%) for the β phenotype; 1031 of 4318 (24%) for the γ phenotype; and 897 of 2223 (40%) for the δ phenotype. Across all cohorts and trials, 28-day and 365-day mortality were highest among the δ phenotype vs the other 3 phenotypes (P 33% chance of benefit to >60% chance of harm). CONCLUSIONS AND RELEVANCE: In this retrospective analysis of data sets from patients with sepsis, 4 clinical phenotypes were identified that correlated with host-response patterns and clinical outcomes, and simulations suggested these phenotypes may help in understanding heterogeneity of treatment effects. Further research is needed to determine the utility of these phenotypes in clinical care and for informing trial design and interpretation.

An adaptive Nesterov acceleration gradient (NAG) algorithm is first developed to extract single generalized principal component (GPC) corresponding to the largest eigenvalue of a stationary sample autocorrelation matrix pencil. A deflation technique enables the proposed algorithm to extract the higher-order GPCs. The proposed algorithm enjoys the advantages of a lower computational load and a highly modular structure for efficient implementation. Simulation results are given to demonstrate the effectiveness of the proposed algorithm for extracting multiple generalized principal components.

Transthoracic Doppler-echocardiography (TTE) can estimate mean pulmonary arterial pressure (MPAP) and pulmonary capillary wedge pressure (PCWP) reliably, and cardiac magnetic resonance (CMR) is the best modality for non-invasive measurement of cardiac output (CO). We speculated that the combined use of TTE and CMR could provide a feasible method for non-invasive measurement of pulmonary vascular resistance (PVR) in pulmonary arterial hypertension (PAH). Right heart catheterization (RHC) was undertaken in 77 patients (17M/60F) with PAH, and simultaneous TTE was carried out to evaluate MPAP, PCWP and CO. Within 2 days, CO was measured again with CMR in similar physiological status. Then, PVR was calculated with the integrated non-invasive method: TTE-derived (MPAP–PCWP)/CMR-derived CO and the isolated TTE method: TTE-derived (MPAP–PCWP)/TTE-derived CO, respectively. The PVR calculated with integrated non-invasive method correlated well with RHC-calculated PVR (r = 0.931, 95% confidence interval 0.893 to 0.956). Between the integrated non-invasive PVR and RHC-calculated PVR, the Bland–Altman analysis showed the satisfactory limits of agreement (mean value: − 0.89 ± 2.59). In comparison, the limits of agreement were less satisfactory between TTE-calculated PVR and RHC-calculated PVR (mean value: − 1.80 ± 3.33). Furthermore, there were excellent intra- and inter-observer correlations for the measurements of TTE and CMR (P < 0.001 for all). The combined use of TTE and CMR provides a clinically reliable method to determine PVR non-invasively. In comparison with RHC, the integrated method shows good accuracy and repeatability, which suggests the potential for the evaluation and serial follow-up in patients with PAH. In PAH, the non-invasive measurement of PVR is very important in clinical practice. Up to now, however, the widely accepted non-invasive method is still unavailable. Since TTE can estimate (MPAP–PCWP) reliably and CMR is the best image modality for the measurement of CO, the combined use of two modalities has the potential to determine PVR non-invasively. In this research, the integrated non-invasive method showed good diagnostic accuracy and repeatability compared with RHC. Therefore, it might be a feasible method for non-invasive measurement of PVR in patients with PAH.

Introduction: Pericardial effusion (PE) without obvious periprocedural complications (e.g., cardiac perforation, device erosion) may occur after transcatheter closure of secundum atrial septal defects (ASD).It has only been described in case reports, and has not been the subject of systematic study. Hypothesis: The aim of the study is to investigate the incidence and predictors of PE unrelated to procedural complications, thus providing interventional cardiologists with a novel way to approach new-onset PE after ASD closure. Methods: We included all patients who had undergone successful percutaneous ASD closure from June 2009 to April 2014 (n=2652) with no preexisting PE or cardiac perforation or erosion. Transthoracic echocardiography (TTE) was performed during the procedure and 1, 3, and 6 months postoperatively. Results: After device implantation, fifty patients (1.9 %) developed new-onset PE (37 immediately, 13 during follow-up). These patients were asymptomatic, stable hemodynamically, and had no new arrhythmias. PE appeared mild (5.1±1.9 mm) and homogeneously echo-lucent by TTE (Figure). PE diminished spontaneously. Compared with 2602 patients without PE, factors independently predicting asymptomatic PE were the device touching the atrial free wall, device size, patient age, and total defect size (Table). Areas under the receiver operating characteristic curves were 0.78 (p Conclusion: A new type of PE is firstly reported systematically. Our data provide new insights into new-onset PE after percutaneous ASD closure.

Two quaternary InAlGaN films were grown by metal-organic chemical-vapor deposition (MOCVD) on sapphire (0001) substrates with and without high-temperature GaN interlayer, respectively. The structural and optical properties of the quaternary films were investigated by high-resolution X-ray diffraction (HRXRD), high-resolution electron microscopy (HREM), temperature-dependent photoluminescence (PL) spectroscopy and time-resolved photoluminescence (TRPL) spectroscopy. According to the HRXRD and PL results, it is demonstrated that two samples have the same crystal quality. The TRPL signals of both samples were fitted well as a stretched exponential decay from 14 K to 250 K, indicating significant disorder in the materials, which is attributed to recombination of excitons localized in disorder quantum nanostructures such as quantum dots or quantum disks originating from indium (In) clusters or In composition fluctuation. The cross-section HREM measurement further proves that there exist disorder quantum nanostructures in the quaternary. By investigating the temperature dependence of the dispersive exponent beta, it is shown that the stretched exponential decays of the two samples originate from different mechanisms. (C) 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The ternary Zn1-xCdxO (0less than or equal toxless than or equal to0.6) alloying films with highly c-axis orientation have been deposited on Si(111) substrates by direct current reactive magnetron sputtering method. X-ray diffraction measurement indicates that the wurtzite-type structure of ZnO can be stabilized up to nominal Cd content x similar to 0.6 without cubic CdO phase separation. The lattice parameter c of Zn1-xCdxO increases almost linearly from 5.229 Angstrom (x = 0) to 5.247 Angstrom (x = 0.6), indicating that Cd substitution takes place on the Zn lattice sites. The photoluminescence spectra of the Zn1-xCdxO thin films measured at 12 K display a substantial red shift (similar to0.3 eV) in the near-band-edges (NBEs) emission of ZnO: from 3.39 eV of ZnO to 3.00 eV of Zn0.4Cd0.6O. The direct modulation of band gap caused by Zn/Cd substitution is responsible for the red shift effect in NBE emission of ZnO. (C) 2003 Elsevier Science B.V. All rights reserved.

The growth interruption (GI) effect on GaSb quantum dot formation grown on GaAs by molecular beam epitaxy was investigated. The structure characterization was performed by reflection high-energy electron diffraction (RHEED), along with photoluminescence measurements. It is found that the GI can significantly change the surface morphology of GaSb QDs. During the GI, the QDs structures can be smoothed out and turned into a 2D-like structure. The time duration of the GI required for the 3D/2D transition depends on the growth time of the GaSb layer. It increases with the increase of the growth time. Our results are explained by a combined effect of the stress relaxation process and surface exchange reactions during the GI. (C) 2002 Elsevier Science B.V. All rights reserved.

Absolute measurement of detector quantum efficiency using optical parametric down-conversion has been extensively studied for the case of a continuous wave pump. In this paper, we have used the temporally and spatially correlated properties of the down-converted photon pairs generated in a nonlinear crystal pumped by a femtosecond laser pulse to perform an absolute measurement of detector quantum efficiency. The measured detector quantum efficiency is in excellent agreement with the measured value in the conventional way. A lens with a long focal length was adopted for efficiently increasing the intensity of the down-conversion entangled photon source.