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Background: Type 2 diabetes mellitus (T2DM) is a major risk factor for coronary artery disease and myocardial infarction (MI). The interaction of diabetic cardiomyopathy and MI scars on myocardial deformation in T2DM patients is unclear. Therefore, we aimed to evaluate myocardial deformation using cardiac magnetic resonance (CMR) in T2DM patients with previous MI and investigated the influence of myocardial scar on left ventricular (LV) deformation. Methods: Overall, 202 T2DM patients, including 46 with MI (T2DM(MI+)) and 156 without MI (T2DM(MI−)), and 59 normal controls who underwent CMR scans were included. Myocardial scars were assessed by late gadolinium enhancement. LV function and deformation, including LV global function index, LV global peak strain (PS), peak systolic strain rate (PSSR), and peak diastolic strain rate (PDSR), were compared among these groups. Correlation and multivariate linear regression analyses were used to investigate the relationship between myocardial scars and LV deformation. Results: Decreases were observed in LV function and LV global PS, PSSR, and PDSR in the T2DM(MI+) group compared with those of the other groups. Reduced LV deformation (p < 0.017) was observed in the T2DM(MI+) group with anterior wall infarction. The increased total LV infarct extent and infarct mass of LV were related to decreased LV global PS (radial, circumferential, and longitudinal directions; p < 0.01) and LV global PSSR (radial and circumferential directions, p < 0.02). Multivariate analysis demonstrated that NYHA functional class and total LV infarct extent were independently associated with LV global radial PS (β = − 0.400 and β = − 0.446, respectively, all p < 0.01; model R2 = 0.37) and circumferential PS (β = 0.339 and β = 0.530, respectively, all p < 0.01; model R2 = 0.41), LV anterior wall infarction was independently associated with LV global longitudinal PS (β = 0.398, p = 0.006). Conclusions: The myocardial scarring size in T2DM patients after MI is negatively correlated with LV global PS and PSSR, particularly in the circumferential direction. Additionally, different MI regions have different effects on the reduction of LV deformation, and relevant clinical evaluations should be strengthened. [ABSTRACT FROM AUTHOR]

Background: Progressive cardiomyopathy accounts for almost all mortality among Duchenne muscular dystrophy (DMD) patients.‍ Thus, our aim was to comprehensively characterize myocardial involvement by investigating the heterogeneity of native T1 mapping in DMD patients using global and regional (including segmental and layer-specific) analysis across a large cohort. Methods: We prospectively enrolled 99 DMD patients (8.8 ± 2.5 years) and 25 matched male healthy controls (9.5 ± 2.5 years). All subjects underwent cardiovascular magnetic resonance (CMR) with cine, T1 mapping and late gadolinium enhancement (LGE) sequences. Native T1 values based on the global and regional myocardium were measured, and LGE was defined. Results: LGE was present in 49 (49%) DMD patients. Global native T1 values were significantly longer in LGE-positive (LGE +) patients than in healthy controls, both in basal slices (1304 ± 55 vs. 1246 ± 27 ms, p < 0.001) and in mid-level slices (1305 ± 57 vs. 1245 ± 37 ms, p < 0.001). No significant difference in global native T1 was found between healthy controls and LGE-negative (LGE−) patients. In segmental analysis, LGE + patients had significantly increased native T1 in all analyzed segments compared to the healthy control group. Meanwhile, the comparison between LGE− patients and healthy controls showed significantly elevated values only in the basal anterolateral segment (1273 ± 62 vs. 1234 ± 40 ms, p = 0.034). Interestingly, the epicardial layer had a significantly higher native T1 in LGE− patients than in healthy controls (p < 0.05), whereas no such pattern was noticed in the global myocardium. Epicardial layer native T1 resulted in the highest diagnostic performance for distinguishing between healthy controls and DMD patients in receiver operating curve analyses (area under the curve [AUC] 0.84 for basal level and 0.85 for middle level) when compared to global native T1 and endocardial layer native T1. Conclusions: Myocardial regional native T1, particularly epicardial native T1, seems to have potential as a novel robust marker of very early cardiac involvement in DMD patients. Trial registration: Chinese Clinical Trial Registry (http://www.chictr.org.cn/index.aspx) ChiCTR1800018340, 09/12/2018, Retrospectively registered. [ABSTRACT FROM AUTHOR]

Background: Progressive cardiomyopathy accounts for almost all mortality among Duchenne muscular dystrophy (DMD) patients.‍ Thus, our aim was to comprehensively characterize myocardial involvement by investigating the heterogeneity of native T1 mapping in DMD patients using global and regional (including segmental and layer-specific) analysis across a large cohort. Methods: We prospectively enrolled 99 DMD patients (8.8 ± 2.5 years) and 25 matched male healthy controls (9.5 ± 2.5 years). All subjects underwent cardiovascular magnetic resonance (CMR) with cine, T1 mapping and late gadolinium enhancement (LGE) sequences. Native T1 values based on the global and regional myocardium were measured, and LGE was defined. Results: LGE was present in 49 (49%) DMD patients. Global native T1 values were significantly longer in LGE-positive (LGE +) patients than in healthy controls, both in basal slices (1304 ± 55 vs. 1246 ± 27 ms, p < 0.001) and in mid-level slices (1305 ± 57 vs. 1245 ± 37 ms, p < 0.001). No significant difference in global native T1 was found between healthy controls and LGE-negative (LGE−) patients. In segmental analysis, LGE + patients had significantly increased native T1 in all analyzed segments compared to the healthy control group. Meanwhile, the comparison between LGE− patients and healthy controls showed significantly elevated values only in the basal anterolateral segment (1273 ± 62 vs. 1234 ± 40 ms, p = 0.034). Interestingly, the epicardial layer had a significantly higher native T1 in LGE− patients than in healthy controls (p < 0.05), whereas no such pattern was noticed in the global myocardium. Epicardial layer native T1 resulted in the highest diagnostic performance for distinguishing between healthy controls and DMD patients in receiver operating curve analyses (area under the curve [AUC] 0.84 for basal level and 0.85 for middle level) when compared to global native T1 and endocardial layer native T1. Conclusions: Myocardial regional native T1, particularly epicardial native T1, seems to have potential as a novel robust marker of very early cardiac involvement in DMD patients. Trial registration: Chinese Clinical Trial Registry (http://www.chictr.org.cn/index.aspx) ChiCTR1800018340, 09/12/2018, Retrospectively registered. [ABSTRACT FROM AUTHOR]

Background: Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome with sex-specific pathophysiology. Estrogen deficiency is believed to be responsible for the development of HFpEF in women. However, estrogen deficiency does not seem to be completely responsible for the differences in HFpEF prevalence between sexes. While diabetes mellitus (DM) frequently coexists with HFpEF in women and is associated with worse outcomes, the changes in myocardial contractility among women with HFpEF and the DM phenotype is yet unknown. Therefore, we aimed to investigate sex-related differences in left ventricular (LV) contractility dysfunction in HFpEF comorbid with DM. Methods: A total of 224 patients who underwent cardiac cine MRI were included in this study. Sex-specific differences in LV structure and function in the context of DM were determined. LV systolic strains (global longitudinal strain [GLS], circumferential strain [GCS] and radial strain [GRS]) were measured using cine MRI. The determinants of impaired myocardial strain for women and men were assessed. Results: The prevalence of DM did not differ between sexes (p > 0.05). Despite a similar LV ejection fraction, women with DM demonstrated a greater LV mass index than women without DM (p = 0.023). The prevalence of LV geometry patterns by sex did not differ in the non-DM subgroup, but there was a trend toward a more abnormal LV geometry in women with DM (p = 0.072). The magnitudes of systolic strains were similar between sexes in the non-DM group (p > 0.05). Nevertheless, in the DM subgroup, there was significant impairment in women in systolic strains compared with men (p < 0.05). In the multivariable analysis, DM was associated with impaired systolic strains in women (GLS [β = 0.26; p = 0.007], GCS [β = 0.31; p < 0.001], and GRS [β = −0.24; p = 0.016]), whereas obesity and coronary artery disease were associated with impaired systolic strains in men (p < 0.05). Conclusions: Women with DM demonstrated greater LV contractile dysfunction, which indicates that women with HFpEF comorbid with DM have a high-risk phenotype of cardiac failure that may require more aggressive and personalized medical treatment. [ABSTRACT FROM AUTHOR]

This study aimed to explore the feasibility and accuracy of single-shot compressed-sensing (CS) cardiac magnetic resonance cine technology for the assessment of biventricular function and morphology in free-breathing (FB) pediatrics, especially those with arrhythmia. Seventy consecutive pediatric participants (6.27 ± 3.8 years, range:0.5–14 years) were enrolled between August 2019 and July 2020. Single-shot CS and conventional balanced steady-state free-precession (bSSFP) cine were obtained. The total scanning time, image quality and biventricular function parameters were compared for both sequences. Single-shot CS cine had shorter acquisition time compared with the conventional bSSFP cine (all P < 0.001). The single-shot CS cine also had fewer artifacts than conventional bSSFP cine (breath-hold (BH): 4.6 ± 0.6 vs. 4.3 ± 0.6; FB without ongoing arrhythmia: 4.5 ± 0.6 vs. 3.6 ± 0.9; FB with ongoing arrhythmia: 4.7 ± 0.5 vs. 2.6 ± 1.1; all P < 0.05). No statistical difference of left ventricular parameters and right ventricular end-systolic volume/ejection fraction were found between the single-shot CS and conventional bSSFP cine in both BH and FB without ongoing arrhythmia group. There was an excellent correlation (R 2 = 0.60–0.98, all P < 0.001) and good intra-(range: R 2 = 0.57–0.99, P < 0.001)/inter-observer agreements (range: R 2 = 0.76–1, P < 0.001) for single-shot CS cine images in terms of biventricular function parameters. The single-shot CS cine can significantly reduce the image acquisition time, offering reliable quantification of biventricular function in free breathing condition for arrhythmic patients. • Single-shot CS cine accelerated the CMR imaging in pediatric patients. • Single-shot CS cine offered accurate quantification of biventricular function with acceptable image quality. • Single-shot CS CMR cine provided an alternative option for free-breathing and arrhythmia children. [ABSTRACT FROM AUTHOR]

Abstract: Detailed knowledge of pulmonary vein (PV) anatomy is essential for successful radiofrequency catheter ablation. The purpose of this study was to evaluate the anatomy of pulmonary veins (PVs) by using dual-source computed tomography (DSCT). 57 patients with and 53 subjects without atrial fibrillation underwent DSCT examination. PV variations were more common in patients than those in subjects (29.8% vs. 13.2%). Early branching occurred more often with right than with left PVs (P <0.01). Size of superior and right PVs ostia was larger than that of inferior and left PVs in patients and subjects (P <0.01), respectively. The ostia of right PVs were more round than those of left PVs (P <0.01). For each PV, the 95% confidence intervals of spatial angles were rather narrow. In conclusion, the variations, ostial size and shape and spatial orientation of PVs could be precisely visualized and adequately evaluated by DSCT. [Copyright &y& Elsevier]

Objective: The aim of this study was to identify the signal molecules involved in IL-1β-induced expression of cyclooxygenase (COX)-2 in human pulmonary epithelial (A549) cells. Methods: A549 cells were stimulated with IL-1β in the presence or absence of H-7 (a protein kinase C inhibitor), SB203580 (a p38 mitogen-activated protein kinase inhibitor) and PD098059 (a mitogen-activated and extracellular regulated kinase kinase (MEK1) inhibitor). The A549 cells were also transfected with adenovirus vector encoding activator protein (AP)-2α, or a plasmid containing a dominant-negative gene (AP-2Δ), in the presence or absence of IL-1β. Results: IL-1β induced expression of the COX-2 mRNA and protein in A549 cells in a time- and dose-dependent manner. SB203580 and H-7, but not PD098059, inhibited IL-1β-induced expression of COX-2 protein. Overexpression of AP-2α increased expression of the COX-2 protein, whereas AP-2Δ decreased IL-1β-induced COX-2 expression. Conclusion: Protein kinase C, p38 mitogen-activated protein kinase and transcriptional factor AP-2α may play important roles in regulating IL-1β-induced COX-2 expression in human pulmonary epithelial cells. [ABSTRACT FROM AUTHOR]

Background: Functional mitral regurgitation (FMR) is one of the most common heart valve diseases in diabetes and may increase left ventricular (LV) preload and aggravate myocardial stiffness. This study aimed to investigate the aggravation of FMR on the deterioration of LV strain in type 2 diabetes mellitus (T2DM) patients and explore the independent indicators of LV peak strain (PS). Materials and methods: In total, 157 T2DM patients (59 patients with and 98 without FMR) and 52 age- and sex-matched healthy control volunteers were included and underwent cardiac magnetic resonance examination. T2DM with FMR patients were divided into T2DM patients with mild (n = 21), moderate (n = 19) and severe (n = 19) regurgitation. LV function and global strain parameters were compared among groups. Multivariate analysis was used to identify the independent indicators of LV PS. Results: The T2DM with FMR had lower LV strain parameters in radial, circumferential and longitudinal direction than both the normal and the T2DM without FMR (all P < 0.05). The mild had mainly decreased peak diastolic strain rate (PDSR) compared to the normal. The moderate had decreased peak systolic strain rate (PSSR) compared to the normal and PDSR compared to the mild and the normal. The severe FMR group had decreased PDSR and PSSR compared to the mild and the normal (all P < 0.05). Multiple linear regression showed that the regurgitation degree was independent associated with radial (β = − 0.272), circumferential (β = − 0.412) and longitudinal (β = − 0.347) PS; the months with diabetes was independently associated with radial (β = − 0.299) and longitudinal (β = − 0.347) PS in T2DM with FMR. Conclusion: FMR may aggravate the deterioration of LV stiffness in T2DM patients, resulting in decline of LV strain and function. The regurgitation degree and months with diabetes were independently correlated with LV global PS in T2DM with FMR. [ABSTRACT FROM AUTHOR]

Background: Tumor mutation burden (TMB) is an emerging prognostic biomarker of immunotherapy for bladder cancer (BLCA). We aim at investigating radiomic features' value in predicting the TMB status of BLCA patients.Methods: Totally, 75 patients with BLCA were enrolled. Radiomic features extracted from the volume of interest of preoperative pelvic contrast-enhanced computed tomography (CECT) were obtained for each case. Unsupervised hierarchical clustering analysis was performed based on radiomic features. Sequential univariate Logistic regression, the least absolute shrinkage and selection operator (LASSO) regression and the backward stepwise regression were used to develop a TMB-predicting model using radiomic features.Results: The unsupervised clustering analysis divided the total cohort into two groups, i.e., group A (32.0%) and B (68.0%). Patients in group A had a significantly larger proportion of having high TMB against those in group B (66.7% vs. 41.2%, p = 0.039), indicating the intrinsic ability of radiomic features in TMB-predicting. In univariate analysis, 27 radiomic features could predict TMB. Based on six radiomic features selected by logistic and LASSO regression, a TMB-predicting model was built and visualized by nomogram. The area under the ROC curve of the model reached 0.853. Besides, the calibration curve and the decision curve also revealed the good performance of the model.Conclusions: Our work firstly proved the feasibility of using radiomics to predict TMB for patients with BLCA. The predictive model based on radiomic features from pelvic CECT has a promising ability to predict TMB. Future study with a larger cohort is needed to verify our findings. [ABSTRACT FROM AUTHOR]

To solve the problem of the small deformation of piezoelectric vibrators and improve the overall performance of piezoelectric micro-pumps, a flexible-diaphragm piezoelectric micropump is designed based on hydraulic amplification. The micropump uses a piezoelectric vibrator to provide its driving force, and fluid is delivered by driving the liquid to amplify the displacement of the piezoelectric vibrator. First, the working principle of the piezoelectric micropump is analyzed, and then theoretical analysis and displacement output tests of the hydraulic amplifier unit are carried out. The test results are consistent with those of the theoretical analysis, and the amplification factor of the hydraulic amplifier unit is 3.29. Finally, prototypes are produced and an experimental platform is built for testing. The results indicate that the best-performing piezoelectric micropump has a self-priming height of 1200 mm, an output pressure of 22.16 kPa, and an output flow of 23.18 ml/min. Compared with an ordinary piezoelectric pump, the overall performance of the piezoelectric micropump is greatly improved. [ABSTRACT FROM AUTHOR]

Objectives: To assess the longitudinal changes of microvascular function in different myocardial regions after myocardial infarction (MI) using myocardial blood flow derived by dynamic CT perfusion (CTP-MBF), and compare CTP-MBF with the results of cardiac magnetic resonance (CMR) and histopathology.Methods: The CTP scanning was performed in a MI porcine model 1 day (n = 15), 7 days (n = 10), and 3 months (n = 5) following induction surgery. CTP-MBF was measured in the infarcted myocardium, penumbra, and remote myocardium, respectively. CMR perfusion and histopathology were performed for validation.Results: From baseline to follow-up scans, CTP-MBF presented a stepwise increase in the infarcted myocardium (68.51 ± 11.04 vs. 86.73 ± 13.32 vs. 109.53 ± 26.64 ml/100 ml/min, p = 0.001) and the penumbra (104.92 ± 29.29 vs. 120.32 ± 24.74 vs. 183.01 ± 57.98 ml/100 ml/min, p = 0.008), but not in the remote myocardium (150.05 ± 35.70 vs. 166.66 ± 38.17 vs. 195.36 ± 49.64 ml/100 ml/min, p = 0.120). The CTP-MBF correlated with max slope (r = 0.584, p < 0.001), max signal intensity (r = 0.357, p < 0.001), and time to max (r = - 0.378, p < 0.001) by CMR perfusion. Moreover, CTP-MBF defined the infarcted myocardium on triphenyl tetrazolium chloride staining (AUC: 0.810, p < 0.001) and correlated with microvascular density on CD31 staining (r = 0.561, p = 0.002).Conclusion: CTP-MBF could quantify the longitudinal changes of microvascular function in different regions of the post-MI myocardium, which demonstrates good agreement with contemporary CMR and histopathological findings.Key Points: • The CT perfusion-based myocardial blood flow (CTP-MBF) could quantify the microvascular impairment in different myocardial regions after myocardial infarction (MI) and track its recovery over time. • The assessment of CTP-MBF is in good agreement with contemporary cardiac MRI and histopathological findings, which potentially facilitates a rapid approach for pathophysiological insights following MI. [ABSTRACT FROM AUTHOR]

Background: Essential hypertension and type 2 diabetes mellitus (T2DM) are two common chronic diseases that often coexist, and both of these diseases can cause heart damage. However, the additive effects of essential hypertension complicated with T2DM on left ventricle (LV) diastolic function have not been fully illustrated. This study aims to investigate whether T2DM affects the diastolic function of the LV in patients with essential hypertension using the volume-time curve from cardiac magnetic resonance (CMR). Methods: A total of 124 essential hypertension patients, including 48 with T2DM [HTN(T2DM +) group] and 76 without T2DM [HTN(T2DM-) group], and 52 normal controls who underwent CMR scans were included in this study. LV volume-time curve parameters, including the peak ejection rate (PER), time to peak ejection rate (PET), peak filling rate (PFR), time to peak filling rate from end-systole (PFT), PER normalized to end-diastolic volume (PER/EDV), and PFR normalized to EDV (PFR/EDV), were measured and compared among the three groups. Multivariate linear regression analyses were performed to determine the effects of T2DM on LV diastolic dysfunction in patients with hypertension. Pearson correlation was used to analyse the correlation between the volume-time curve and myocardial strain parameters. Results: PFR and PFR/EDV decreased from the control group, through HTN(T2DM −), to HTN(T2DM +) group. PFT in the HTN(T2DM-) group and HTN(T2DM +) group was significantly longer than that in the control group. The LV remodelling index in the HTN(T2DM −) and HTN(T2DM +) groups was higher than that in the normal control group, but there was no significant difference between the HTN(T2DM −) and HTN(T2DM +) groups. Multiple regression analyses controlling for covariates of systolic blood pressure, age, sex, and heart rate demonstrated that T2DM was independently associated with PFR/EDV (β = 0.252, p < 0.05). The volume-time curve method has good repeatability, and there is a significant correlation between volume-time curve parameters (PER/EDV and PFR/EDV) and myocardial peak strain rate, especially circumferential peak strain rate, which exhibited the highest correlation (r = − 0.756 ~ 0.795). Conclusions: T2DM exacerbates LV diastolic dysfunction in patients with essential hypertension. The LV filling model changes reflected by the CMR volume-time curve could provide more information for early clinical intervention. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of mitral regurgitation (MR) on cardiac structure and function in left ventricular noncompaction (LVNC) patients. The clinical and cardiovascular magnetic resonance (CMR) data for 182 patients with noncompaction or hypertrabeculation from three institutes were retrospectively included. We analyzed the difference in left ventricular geometry, cardiac function between LVNC patients with and without MR. The results showed that patients with MR had a worse New York Heart Association (NYHA) class and a higher incidence of arrhythmia (P < 0.05). MR occurred in 48.2% of LVNC patients. Compared to LVNC patients without MR, the two-dimensional sphericity index, maximum/minimum end-diastolic ratio and longitudinal shortening in LVNC patients with MR were lower (P < 0.05), and the peak longitudinal strain (PLS) of the global and segmental myocardium were obviously reduced (P < 0.05). No significant difference was found in strain in LVNC patients with different degree of MR; end diastolic volume, end systolic volume, and global PLS were statistically associated with MR and NYHA class (P < 0.05), but the non-compacted to compacted myocardium ratio had no significant correlation with them. In conclusion, the presence of MR is common in LVNC patients. LVNC patients with MR feature more severe morphological and functional changes. Hypertrabeculation is not an important factor affecting structure and function at the heart failure stage. [ABSTRACT FROM AUTHOR]

Background: Patients with type 2 diabetes mellitus (T2DM) are susceptible to coexisted with chronic kidney disease (CKD), which may increase cardiovascular mortality in these patients. The present study aimed to verify whether CKD aggravates the deterioration of left ventricular (LV) myocardial strain in T2DM patients and to explore the risk factors associated with LV strain. Materials and methods: In total, 105 T2DM patients and 52 healthy individuals were included and underwent cardiac magnetic resonance examination. Patients were divided into the following two groups: T2DM with CKD (n = 33) and T2DM without CKD (n = 72). The baseline clinical and biochemical indices were obtained from hospital records before the cardiac magnetic resonance scan. Cine sequences, including long-axis views (2-chamber and 4-chamber) and short-axis views, were acquired. LV function and global strain parameters were measured based on cine sequences and compared among three groups. Pearson's analysis was performed to investigate the correlation between LV strain parameters and clinical indices. Multiple linear regression analysis was used to identify the independent indicators of LV strain. Results: Compared with normal controls, T2DM patients without CKD had a significantly decreased magnitude of peak strain (PS; radial), peak systolic strain rate (radial), and peak diastolic strain rate (radial and circumferential) (all P < 0.05). Furthermore, T2DM patients with CKD displayed markedly lower magnitudes of PS (radial, circumferential, and longitudinal) and peak diastolic strain rate (circumferential and longitudinal) than both normal controls and T2DM patients without CKD (all P < 0.05). The eGFR was positively associated with the magnitude of PS (R = radial, 0.392; circumferential, 0.436; longitudinal, 0.556), while uric acid was negatively associated with the magnitude of PS (R = radial, − 0.361; circumferential, − 0.391; longitudinal, − 0.460) (all P < 0.001). Multivariable linear regression indicated that the magnitude of PS was independently associated with eGFR (β = radial, 0.314; circumferential, 0.292; longitudinal, 0.500) and uric acid (β = radial, − 0.239; circumferential, − 0.211; longitudinal, − 0.238) (all P < 0.05). Conclusions: Kidney dysfunction may aggravate the deterioration of LV strain in T2DM patients. LV strain is positively associated with the estimated glomerular filtration rate and negatively associated with uric acid, which may be independent risk factors for predicting reduction of LV strain. [ABSTRACT FROM AUTHOR]

Diabetes mellitus-related cardiomyopathy has recently been described as a distinct progression of left ventricular (LV) systolic and diastolic dysfunction. Pathological changes in the myocardium may explain the development of two different phenotypes. We evaluated the effects of LV geometry, myocardial microcirculation, and tissue characteristics on cardiac deformation in patients with subclinical type 2 diabetes mellitus (T2DM) utilizing multiparametric cardiac magnetic resonance (CMR) imaging. A total of 135 T2DM patients and 55 matched controls were prospectively enrolled and performed multiparametric CMR examination. CMR-derived parameters including cardiac geometry, function, microvascular perfusion, T1 mapping, T2 mapping, and strain were analyzed and compared between T2DM patients and controls. The univariable and multivariable analysis of systolic and diastolic function revealed that longer duration of diabetes was associated with decreased longitudinal peak systolic strain rate (PSSR-L) (β = 0.195, p =.013), and higher remodeling index and higher extracellular volume (ECV) tended to correlate with decreased longitudinal peak diastolic strain rate (PDSR-L) (remodeling index, β = −0.339, p =.000; ECV, β = −0.172, p =.026), whereas microvascular perfusion index and T2 value affected both PSSR-L (perfusion index, β = −0.328, p =.000; T2 value, β = 0.306, p =.000) and PDSR-L (perfusion index, β = 0.209, p =.004; T2 value, β = −0.275, p =.000) simultaneously. The LV concentric remodeling and myocardial fibrosis correlated with diastolic function, and perfusion function and myocardial edema were associated with both LV systolic and diastolic function. • Diabetes causes disturbance in cardiac structure, perfusion, tissue and function. • Cardiac subunits presented diverse effects on systolic and diastolic function. • Left ventricular concentric remodeling and fibrosis affect diastolic function. • Myocardial perfusion and edema corresponded with systolic and diastolic function. • The duration of diabetes affects systolic function by acting on certain mechanisms. [ABSTRACT FROM AUTHOR]

To give a basic understanding of the experimentally observed difference between Cr2O3 and Al2O3 scales on carbon permeation, we employed the first-principles calculation methods to predict atomistic structures, formation energies, and carbon binding energies of Σ11 10 1 ¯ 1 / 10 1 ¯ 1 ¯ tilt grain boundaries (GB) in both α-Al2O3 and α-Cr2O3 with a corundum structure. Owing to different surface terminations, we predicted two distinct kinds of stable atomistic structures for the GB: one with measurable voids and high formation energy, and the other with a compact interface and low formation energy. The predicted GB structures agree with experimental images. No significant structural difference was found for the same GB in α-Al2O3 and α-Cr2O3. Moreover, we predicted that atomic carbon would bind to the Σ11 10 1 ¯ 1 / 10 1 ¯ 1 ¯ GB in α-Cr2O3 appreciably more strongly than in α-Al2O3. Therefore, our computational results suggest that chemical affinity rather than geometric structure of the GBs is related to different carbon permeation behaviors in Al2O3 and Cr2O3 scales. [ABSTRACT FROM AUTHOR]

The original version of this article, published on 27 May 2019, unfortunately contained mistakes. [ABSTRACT FROM AUTHOR]

To quantify the global and regional left ventricular (LV) myocardial strain in type 2 diabetes mellitus (T2DM) patients using cardiac magnetic resonance (CMR) tissue-tracking techniques and to determine the ability of myocardial strain parameters to assessment the LV deformation. Our study included 98 adult T2DM patients (preserved LV ejection fraction [LVEF], 72; reduced LVEF, 26) and 35 healthy controls. Conventional LV function, volume-time curve parameters and LV remodeling index were measured using CMR. Global and regional LV myocardial strain parameters were measured using CMR tissue tracking and compared between the different sub-groups. Receiver operating characteristic analysis was used to assess the diagnostic accuracy. Regression analyses were conducted to determine the relationship between strain parameters and the LV remodeling index. The results show that global radial peak strain (PS) and circumferential PS were not significantly different between the preserved-LVEF group and control group (P > 0.05). However, longitudinal PS was significantly lower in the preserved-LVEF group than in the control group (P = 0.005). Multivariate linear and logistic regression analyses showed that global longitudinal PS was independently associated (β = 0.385, P < 0.001) with the LV remodeling index. In conclusion, early quantitative evaluation of cardiac deformation can be successfully performed using CMR tissue tracking in T2DM patients. In addition, global longitudinal PS can complement LVEF in the assessment of cardiac function. [ABSTRACT FROM AUTHOR]

In the current urban rail transit systems, nearly 15% of passengers are noncommuter travelers who use single-trip ticket cards (ticket cards). Accordingly, the effective management of ticket cards is of great importance. This article suggests a time series model for use in predicting ticket card storage based on the characteristics of ticket cards collected by an automatic fare collection (AFC) system. The distribution cycle, station types, and distribution volume of each station are also determined. Then, drawing on small package transportation feasibility theory, an unbalanced distribution model between production and demand (unbalanced distribution model), as well as a hybrid distribution model of loading and unloading (hybrid distribution model), is established. Application of these models to the Beijing Subway system is used to verify the efficiency and feasibility of such a hybrid distribution model. The analysis and results offer insights into usage patterns of urban rail transit ticket cards, providing solid evidence for a relative decision-making process. [ABSTRACT FROM AUTHOR]

Background: Metabolic syndrome (MetS) is a cluster of metabolic abnormalities that collectively cause an increased risk of type 2 diabetes mellitus (T2DM) and nonatherosclerotic cardiovascular disease. This study aimed to evaluate the role of myocardial steatosis in T2DM patients with or without MetS, as well as the relationship between subclinical left ventricular (LV) myocardial dysfunction and myocardial steatosis. Methods and materials: We recruited 53 T2DM patients and 20 healthy controls underwent cardiac magnetic resonance examination. All T2DM patients were subdivide into two group: MetS group and non-MetS. LV deformation, perfusion parameters and myocardial triglyceride (TG) content were measured and compared among these three groups. Pearson's and Spearman analysis were performed to investigate the correlation between LV cardiac parameters and myocardial steatosis. The receiver operating characteristic curve (ROC) was performed to illustrate the relationship between myocardial steatosis and LV subclinical myocardial dysfunction. Results: An increase in myocardial TG content was found in the MetS group compared with that in the other groups (MetS vs. non-MetS: 1.54 ± 0.63% vs. 1.16 ± 0.45%; MetS vs. normal: 1.54 ± 0.63% vs. 0.61 ± 0.22%; all p < 0.001). Furthermore, reduced LV deformation [reduced longitudinal and radial peak strain (PS); all p < 0.017] and microvascular dysfunction [increased time to maximum signal intensity (TTM) and reduced Upslope; all p < 0.017)] was found in the MetS group. Myocardial TG content was positively associated with MetS (r = 0.314, p < 0.001), and it was independently associated with TTM (β = 0.441, p < 0.001) and LV longitudinal PS (β = 0.323, p = 0.021). ROC analysis exhibited that myocardial TG content might predict the risk of decreased LV longitudinal myocardial deformation (AUC = 0.74) and perfusion function (AUC = 0.71). Conclusion: Myocardial TG content increased in T2DM patients with concurrent MetS. Myocardial steatosis was positively associated with decreased myocardial deformation and perfusion dysfunction, which may be an indicator for predicting diabetic cardiomyopathy. [ABSTRACT FROM AUTHOR]

Background: The microvascular effects of obesity should be considered in diabetic individuals for elucidating underlying mechanisms and developing targeted therapies. This study aims to determine the effect of obesity on myocardial microvascular function in type 2 diabetes mellitus (T2DM) patients using cardiac magnetic resonance (CMR) first-pass perfusion imaging and assessed significant risk factors for microvascular dysfunction. Materials and methods: Between September 2016 and May 2018, 120 patients with T2DM (45.8% women [55 of 120]; mean age, 56.45 ± 11.97 years) and 79 controls (44.3% women [35 of 79]; mean age, 54.50 ± 7.79 years) with different body mass index (BMI) scales were prospectively enrolled and underwent CMR examination. CMR-derived perfusion parameters, including upslope, time to maximum signal intensity (TTM), maximum signal intensity (MaxSI), MaxSI (-baseline), and SI (baseline), and T2DM related risk factors were analyzed among groups/subgroups both in T2DM patients and controls. Univariable and multivariable linear and logistic regression analyses were performed to assess the potential additive effect of obesity on microvascular dysfunction in diabetic individuals. Results: Compared with controls with comparable BMIs, patients with T2DM showed reduced upslope and MaxSI and increased TTM. For both T2DM and control subgroups, perfusion function gradually declined with increasing BMI, which was confirmed by all perfusion parameters, except for TTM (all P < 0.01). In multivariable linear regression analysis, BMI (β = − 0.516; 95% confidence interval [CI], − 0.632 to − 0.357; P < 0.001), female sex (β = 0.372; 95% CI, 0.215 to 0.475; P < 0.001), diabetes duration (β = − 0.169; 95% CI, − 0.319 to − 0.025; P = 0.022) and glycated haemoglobin (β = − 0.184; 95% CI, − 0.281 to − 0.039; P = 0.010) were significantly associated with global upslope in the T2DM group. Multivariable logistic regression analysis indicated that T2DM was an independent predictor of microvascular dysfunction in normal-weight (odds ratio[OR], 6.46; 95% CI, 2.08 to 20.10; P = 0.001), overweight (OR, 7.19; 95% CI, 1.67 to 31.07; P = 0.008) and obese participants (OR, 11.21; 95% CI, 2.38 to 52.75; P = 0.002). Conclusions: Myocardial microvascular function gradually declined with increasing BMI in both diabetes and non-diabetes status. T2DM was associated with an increased risk of microvascular dysfunction, and obesity exacerbated the adverse effect of T2DM. [ABSTRACT FROM AUTHOR]

Differentiating cardiac amyloidosis (CA) from hypertrophic cardiomyopathy (HCM) remains a clinical challenge, particularly in those with preserved left ventricular ejection fraction (LVEF) and similar hypertrophy. This study aimed to use left ventricular global function index (LVGFI) and myocardial contraction fraction (MCF) to discriminate CA from HCM without using contrast agents on cardiovascular magnetic resonance imaging (CMR). In total, we included 68 CA patients, 90 HCM patients, and 35 healthy controls. We found that LVGFI had excellent diagnostic performance in differentiating CA from HCM (area under the curve (AUC) = 0.91, 95% CI [0.86–0.95]), even in the challenging conditions of similar hypertrophy (AUC = 0.92, 95% CI [0.87–0.97]) and preserved LVEF (AUC = 0.90, 95% CI [0.84–0.96]). LVGFI also had significant correlations with LGE extent, NT-proBNP and troponin T (all p < 0.001). Multiple logistic regression analysis revealed that LVGFI was an independent predictor of CA (odds ratio: 1.11, 95% CI: 1.01–1.23; p = 0.034). In conclusion, LVGFI is a novel and clinically useful parameters with excellent ability in determining myocardial function and differentiating cardiac amyloidosis from hypertrophic cardiomyopathy. [ABSTRACT FROM AUTHOR]

Objective: Right ventricular function (RVF) is a strong predictor of adverse cardiac events; however, the reference standard for RVF assessment, MRI, is limited in some patients for whom accurate evaluation of RVF is essential, like those with COPD or non-MR compatible metal implants. We conducted this meta-analysis to evaluate whether CT was as accurate as MRI for the assessment of RVF.Method: We conducted a meta-analysis of studies retrieved from PubMed, Embase, and Cochrane Central searches to evaluate the differences and correlations between the following RVF parameters as measured by CT and MRI: end diastole volume (EDV), end systole volume (ESV), right ventricular ejection fraction (RVEF), and stroke volume (SV).Results: Sixteen studies that used disk summation (637 subjects) and three studies that used three-dimensional reconstruction were included. For the 16 studies, the pooled standard mean differences (95% confidence interval) were 1.04 (- 2.59, 4.67) for EDV, 1.22 (1.50, 3.95) for ESV, - 0.65 (- 2.60, 1.29) for RVEF, and - 0.37 (- 3.64, 2.90) for SV. The overall correlation coefficient (r) values were 0.98 for EDV, 0.95 for ESV, 0.98 for RVEF, and 0.97 for SV. The mean difference between the two methods was not statistically significant (overall effect Z test, p > 0.1).Conclusion: CT can assess RVF with accuracy comparable to that of MRI. Thus, CT is a valid alternative to MRI.Key Points: • CT could help clinicians to assess RVF as accurately as MRI can, with satisfactory repeatability. [ABSTRACT FROM AUTHOR]

• Emodin from R. palmatum presented significant insecticidal activities against N. lugens and M. separate. • Emodin could be used as alternative environmentally bio-insecticide. • Plumbagin demonstrated the strong antifungal activity and a wide antifungal spectrum. • Plumbagin could be used as alternative fungicide for crop protection. As a well-known herb worldwide, rhubarb presents a wide range of pharmacological activities. In our studies, Rheum palmatum L. extracts and five isolated anthraquinones possessed insecticidal activity. The acetone extract (yield, 8.84%), which contained the highest amount of compounds (82.87 mg/g), showed stronger insecticidal activity than did the aqueous extract (yield, 37.17%) and the ethanol extract (yield, 36.92%). Notable amounts of compounds were also found in water extract residues (18.2 mg/g). Among the isolated quinones and structurally related compounds, emodin exhibited the highest insecticidal activity (LC 50 = 84.30 μg/mL) against Nilarparvata lugens ; and very moderate activity against Mythimna separata (LC 50 = 548.74 μg/mL). The LC 50 values of positive agent toosendanin against two insects were 89.34 and 418.24 μg/mL, respectively. Moreover, emodin exhibited significant AChE and GST inhibitory activities (with respective IC 50 values of 11.36 and 4.18 μg/mL). Plumbagin exhibited stronger and broader antifungal activity against eight phytopathogenic fungi (with EC 50 values ranging from 2.84 to 10.53 μg/mL) compared to a commercial fungicide, azoxystrobin (EC 50 ranging from 20.40 to >100.00 μg/mL). Plumbagin significantly damaged the cell and mitochondrial membrane systems, changed the morphology, triggered the release of cellular contents and generate reactive oxygen species in Rhizoctonia solani mycelia. This study laid the foundation for the future development of emodin and plumbagin as alternative, environmentally friendly bioinsecticide and biofungicide, respectively. Rhubarb and its residues can be used as renewable sources of anthraquinone-based products. [ABSTRACT FROM AUTHOR]

Background: Patients with Diabetes mellitus (DM) are susceptible to coronary artery disease (CAD). However, the impact of DM on plaque progression in the non-stented segments of stent-implanted patients has been rarely reported. This study aimed to evaluate the impact of DM on the prevalence, characteristics and severity of coronary computed tomography angiography (CCTA) verified plaque progression in stented patients. A comparison between diabetic and non-diabetic patients was performed. Methods: A total of 98 patients who underwent clinically indicated serial CCTAs arranged within 1 month before and at least 6 months after percutaneous coronary intervention (PCI) were consecutively included. All the subjects were categorized into diabetic group (n = 36) and non-diabetic groups (n = 62). Coronary stenosis extent scores, segment involvement scores (SIS), segment stenosis scores (SSS) at baseline and follow-up CCTA were quantitatively assessed. The prevalence, characteristics and severity of plaque progression was evaluated blindly to the clinical data and compared between the groups. Results: During the median 1.5 year follow up, a larger number of patients (72.2% vs 40.3%, P = 0.002), more non-stented vessels (55.7% vs 23.2%, P < 0.001) and non-stented segments (10.3% vs 4.4%, P < 0.001) showed plaque progression in DM group, compared to non-DM controls. More progressive lesions in DM patients were found to be non-calcified plaques (31.1% vs 12.8%, P = 0.014) or non-stenotic segments (6.6% vs 3.0%, p = 0.005) and were more widely distributed on left main artery (24.2% vs 5.2%, p = 0.007), the right coronary artery (50% vs 21.1%, P = 0.028) and the proximal left anterior artery (33.3% vs 5.1%, P = 0.009) compared to non-DM patients. In addition, DM patients possessed higher numbers of progressive segments per patient, ΔSIS and ΔSSS compared with non-DM individuals (P < 0.001, P = 0.029 and P < 0.001 respectively). A larger number of patients with at least two progressive lesions were found in the DM group (P = 0.006). Multivariate logistic regression analysis demonstrated that DM (OR: 4.81; 95% CI 1.64–14.07, P = 0.004) was independently associated with plaque progression. Conclusions: DM is closely associated with the prevalence and severity of CCTA verified CAD progression. These findings suggest that physicians should pay attention to non-stent segments and the management of non-stent segment plaque progression, particularly to DM patients. [ABSTRACT FROM AUTHOR]

To evaluate the value of dual-source computed tomography (DSCT) compared with transthoracic echocardiography (TTE) in assessing intracardiac and extracardiac anomalies in patients with coarctation of aorta (CoA) and interrupted aortic arch (IAA). Seventy-five patients (63 with CoA and 12 with IAA) who received preoperative DSCT and TTE were retrospectively studied. Intracardiac and extracardiac anomalies were recorded and compared by DSCT and TTE, in reference to surgical or cardiac catheterization findings. A total of 155 associated anomalies were finally found. Collateral circulation (56, 74.70%), patent ductus arteriosus (PDA; 41, 54.67%) were the most common anomalies. PDA, aortopulmonary window, and collateral circulation were more frequently present in patients with IAA than those with CoA (100% vs. 46.03%, 16.67% vs. 0%, and 100% vs. 69.84%, respectively, all p < 0.05). DSCT was superior to TTE in assessing associated extracardiac-vascular anomalies (sensitivity: 100% vs. 39.81%; specificity: 100% vs. 100%; positive predictive value: 100% vs. 100%; negative predictive value: 100% vs. 76.06%). Extracardiac-vascular anomalies, including collateral circulation and PDA, were the most common anomalies in patients with IAA and CoA. Compared with TTE, DSCT is more reliable in providing an overall preoperative evaluation of morphological features and extracardiac anomalies for surgical planning. [ABSTRACT FROM AUTHOR]

The microstructure of the oxides formed on F91 steel upon breakaway oxidation in air and CO2 at 700 °C was characterized and compared. It was observed that the Cr-rich corundum layer became humped and disrupted upon breakaway oxidation in air in the first stage. In contrast, spinel was found to form in CO2 without any humping of the Cr-rich layer upon breakaway oxidation. Whether or not the humping and disrupting of the Cr-rich layer were present was related to the form of oxide. Specifically, corundum oxide was facile in air, whereas spinel oxide was facile in CO2. [ABSTRACT FROM AUTHOR]

Abstract The steady-state assumption in the classical solute drag (SD) models is not always valid in treating the complex interaction between alloying elements and migrating interfaces (grain/phase boundaries) in steels. In this study, a general treatment based on phase-field theory is proposed to capture the SD effects of alloying elements without the steady state assumption, while it reduces to the SD models under steady-state assumption. This new treatment can predict the interaction between migrating interfaces and alloying elements with strong segregation tendencies, which cannot be captured by the classical SD models. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Upon exposure to CO2 at 550 °C, F91 tends to form rapidly growing scales consisting of an outer Fe oxide and an inner Fe-Cr spinel oxide. A comparative study has been carried out between the pre-oxidized and non-pre-oxidized F91, to determine the influence of pre-oxidation upon the oxidation behavior of F91 in CO2. Formation of a rapidly growing scale and carburization could be inhibited by a pre-oxidation treatment in air prior to oxidation in CO2. Although during exposure to CO2, a fast growing scale still would form locally, pre-oxidation changed its structure. Effects of pre-oxidation time on the oxidation resistance in CO2 are investigated. [ABSTRACT FROM AUTHOR]

The oxidation behavior of three commercial superalloys, CrMoV, F91 and Mar-M247, was studied at 550 °C in laboratory air for 1000 h. Mar-M247 superalloy showed the best oxidation resistance, which is attributed to the formation of a scale rich in Cr2O3 and Al2O3, followed by F91 and CrMoV. A thick duplex oxide formed on CrMoV alloy and spallation was observed. The results for CrMoV alloy showed that calculated Fe diffusion in magnetite was 200 times faster than literature values for Fe diffusion in Fe3O4, which is attributed to grain-boundary diffusion and the effect of impurity on diffusion. F91 initially formed a protective chromium-rich oxide layer followed by formation nodules, leading breakaway oxidation. The oxide nodules consisted of a duplex structure with different morphologies and oxide phases from duplex oxide scale in CrMoV. [ABSTRACT FROM AUTHOR]

To determine the feasibility of deformation analysis in the right ventricle (RV) using cardiovascular magnetic resonance myocardial feature tracking (CMR-FT) in type 2 diabetes mellitus (T2DM) patients. We enrolled 104 T2DM patients, including 14 with impaired right ventricular ejection fraction (RVEF) and 90 with preserved RVEF, and 26 healthy controls in this prospective study. CMR was used to determine RV feature-tracking parameters. RV strain parameters were compared among the controls, patients with preserved and reduced RVEF. Binary logistic regression was used to predict RV dysfunction. Receiver operating characteristic analysis was used to assess the diagnostic accuracy. The agreement was tested by Bland–Altman analysis. Compared with controls, longitudinal and circumferential global peak strain (PS) and PS at mid-ventricular, apical slices were significantly decreased in T2DM patients with or without reduced RVEF (p < 0.05). Within the T2DM patients, the global longitudinal PS (GLPS) and the longitudinal PS at mid-ventricular segments were significantly reduced in the reduced RVEF group than in preserved RVEF groups (p < 0.05). GLPS was an independent predictor of RV dysfunction (odds ratio: 1.246, 95% CI: 1.037–1.496; p = 0.019). The GLPS demonstrated greater diagnostic accuracy (area under curve: 0.716) to predict RV dysfunction. On Bland-Altman analysis, global circumferential PS and GLPS had the best intra- and inter-observer agreement, respectively. In T2DM patients, CMR-FT could quantify RV deformation and identify subclinical RV dysfunction in those with normal RVEF. Further, RV strain parameters are potential predictors for RV dysfunction in T2DM patients. [ABSTRACT FROM AUTHOR]

Although tailoring stacking fault energy (SFE) through the addition of suitable alloying element can improve mechanical properties, the effect of strain must also be included to account for the Co-based alloy design. Using first-principles density-functional-theory calculations, we revealed that there is a strong effect of the strain (volumetric strain, simple strain, and volume conserving) and external pressure on the intrinsic SFE of face-centered cubic (fcc) cobalt. This result indicated a new insight into the Co-based alloys design, especially for application at high pressure and severe plastic deformation. The intrinsic SFE decreased by increasing tensile strain or decreasing pressure, thus the tendency of forming stacking faults increases which improves the mechanical properties. Effect of volumetric (hydrostatic) strain is the strongest indicated that the volume is the dominant factor in determining the SFE and the strain-induced fcc-hcp phase transformation. Different strain methods give different charge transfer between adjacent atoms and then contribute to the variation of the atomic bonding at the specific direction and SFE behavior. Application of external pressure from 0 to 15 GPa increased the elastic constants and elastic modulus of fcc Co and then improved the ductility. [ABSTRACT FROM AUTHOR]

Segregation of solute atoms to stacking faults (Suzuki segregation) and their interactions are of longstanding attention since it has a deep impact on mechanical properties. In this study, we systematically investigate the segregation behavior of different solute atoms in fcc Co-based binary alloys and its effect on the intrinsic stacking fault energy (SFE) using first-principles density-functional-theory (DFT) calculations. Interestingly, while Mo, W, Cr, Mn and Al atoms have a strong tendency to Suzuki segregation with some significant energy barriers, Ni atom has no tendency of segregation and only Fe atom has extremely low energy barriers. A strong segregation effect on the intrinsic SFE was observed and it only extends at a few atomic layers in the vicinity of the intrinsic stacking fault plane. The results are consistent with observed solute segregation in similar alloys and commercial superalloys then it would be useful for SFE modeling and Co-based alloys design. Furthermore, the effect of solute concentrations and changes in the electronic features (charge density difference and density of states) are also investigated. A mutual interaction between solutes and stacking faults enhanced local bonding between the solute atom and the adjacent Co atoms, resulted in the lower intrinsic SFE, thus favoring Suzuki segregation. [ABSTRACT FROM AUTHOR]

In the pond culture of juvenile Eriocheir sinensis , various factors have frequently led to a high rate of autotomy and limb impairments. This study evaluated the differential effects of cheliped loss with autotomy and ablation on the short-term cellular and biochemical parameters of juvenile E. sinensis . In this study, compared with the crabs before treatment, the total hemocyte counts (THC), granulocyte counts (GC), hemocyte agglutination, phosphatase activity and glucose metabolism levels were significantly increased, while hyalinocyte counts (HC) and total antioxidant capacity (T-AOC) were significantly decreased within 3 h. However, the THC levels, hemocyte agglutination and hemocyte proliferation were significantly higher in the ablation group within 3 h compared to the autotomy group. Moreover, the changes of glucose metabolism and immune-related enzymes activities in ablation groups were later than autotomy groups. The bacterial challenge showed that the mortality rate of the ablation group was significantly higher than that of the autotomy group. Therefore, the observations in this study indicate that compared with the passive trauma response of ablation, autotomy is a congenital, efficient, and active trauma response mechanism, which is of great significance to the survival and growth of E. sinensis . [ABSTRACT FROM AUTHOR]

Theoretical calculation of stacking fault energy (SFE) needs to be investigated closely in each alloy system due to the complex effect between different elements. In this study, we have revealed that the computational thermodynamic approach and first-principles density-functional-theory (DFT) calculations are capable of calculating the SFE for developing and designing ternary Co-based alloys with low SFE and excellent mechanical properties. Interaction between Ni and Cr atoms in ternary systems can make a distinct effect to the SFE while interaction between Cr and Mo atoms gives more charge transfer then lower the SFE. Effect of alloying atom position and Cr concentrations of Co-Cr-W alloys was studied and explained regarding the electronic structure. In high Cr concentrations, Cr atoms that dispersing uniform are more useful to improving the strengthening effect than those dispersing segregatively. [ABSTRACT FROM AUTHOR]

The kinetics and microstructure of composite coatings on H13 steel in different chemical compositions of baths were studied in the present research. Three metal baths and three oxide baths with chromium to vanadium molar ratios of 0.5, 1 and 2 were used. The coating process was performed at seven different times at 1000 °C for all the baths. Field emission scanning electron microscopy (FE-SEM), electron probe micro analyzer (EPMA) and X-ray diffraction analysis (XRD) were applied to study the coatings. The coating produced in the metal bath had a greater thickness than that in the oxide bath in all the experiments. Before 1 h and between 1 h to 12 h of the coating process, the interface and the diffusion controlled the growth, respectively. Regarding this mechanism of growth, before 1 h, the relationship between coating thickness and time was fitted to a linear function (d = at + b) and from 1 h to 12 h, it was fitted to a parabolic function (d = ct 0.5 + e). Chromium carbide and vanadium carbide coatings grew as columnar and equiaxed grains, respectively. Distribution of chromium carbide-rich regions in vanadium carbide-rich regions became more homogenous with time and a composite coating was formed. [ABSTRACT FROM AUTHOR]

Clinically, early diagnosis and treatment is important for survival of pediatric with vascular ring (VR) associated with congenital heart disease (CHD), and accurate evaluation of VR is a prerequisite for repair surgical. The study aimed to assess the quantitative characteristics of tracheal compression in pediatrics with VR and CHD using dual-source computed tomography (DSCT), and further provided effective information for surgical decisions. A total of 49 VR patients with CHD and 56 controls were enrolled. The tracheal quantitative measurements (short diameter, long diameter, tracheal area and tracheal length) were obtained, and the degree of tracheal compression was assessed. Our results indicated that VR associated with CHD may cause more serious and complex symptoms, and the greater tracheal compression were found on DSCT when more severe symptoms were present (r = 0.84). The degree of tracheal compression was significantly different within the VR group between those with and without surgery (P = 0.002). Finally, there were good agreement among (1-long diameter ratio), (1-short diameter ratio) and (1-area ratio) in patients and controls, respectively. This study indicated that DSCT enables provides accurate quantitative tracheal compression information for VR pediatrics associated with CHD, and evaluation of the degree of tracheal compression by 1-area ratio may contribute to the repair surgical of VR. [ABSTRACT FROM AUTHOR]

The structures and working principles of a piezoelectric pump with dual vibrators are described in this paper. The output performance of the pump was analyses under different working modes. The experimental results demonstrate that changing the driving strategy can vary the performance. When the driving voltage is 60 V at 160 Hz, the maximum output pressure of the pump in the asynchronous mode is 2.18 kPa. The performance of the upper actuator working alone is better than the lower actuator working alone, and the maximum output pressure in this case is 1.3 kPa. Taking the piezoelectric pump with a single vibrator as a typical example, an optimal design method has been applied on the check valves. The performance of the pump with wheel valves is better than that with cantilever valves; the optimum thickness of the check valves is 0.188 mm. [ABSTRACT FROM AUTHOR]

The atomic-scale microstructural and compositional modification of materials are one of the most promising developments of modern materials science. In the present study, we investigate the stacking fault energy (SFE) variations of binary Co-based alloys with different alloying elements (Cr, W, Mo, Ni, Mn, Al and Fe) and concentrations (from 0 to 20 at.%) over a broad range of temperatures (from 0 to 1000 K) by computational thermodynamic approach and first-principles density-functional-theory (DFT) calculations combined with quasi-harmonic approximation (QHA). Our work presents a fundamental understanding of the theoretical SFE calculation and the deviations involved in computational thermodynamic approach and first-principles calculations systematically for the first time. It concludes that the SFEs of binary Co-based alloys are increased as the increased of temperature, Ni, Mn, Al and Fe concentrations while the SFEs are decreased as the increased of Cr, W and Mo concentrations qualitatively. Quantitatively, the SFE differences of these two methods are relatively small (lower than 27 mJ/m 2 ). The SFE variations can be explained regarding the charge density distributions and the atomic bonding. These results also highlight the critical role of Suzuki effect and the key for the SFE variations is the alloying elements only in the vicinity of the fault plane. [ABSTRACT FROM AUTHOR]

The generalized-stacking-fault-energy (GSFE) curve for pure Cobalt and Co-9 at.% X solid-solution alloys (X = Cr, W, Mo, Ni, Mn, Al, Fe) have been successfully calculated by rigidly shearing an fcc crystal at a (1 1 1) plane along a [1 1 −2] slip direction in two processes using first-principles density-functional-theory (DFT), provide a highly accurate modeling and a fairly good agreement with available experimental and other theoretical results in the literature. The objectives of this study are to provide a useful guideline for the Co-based alloy design with superior performances and new insight for understanding the nature of the fcc to hcp phase transformation. Evaluation of the GSFE values is based on the ratio of the stable and unstable stacking fault energy, the twinnabilities with three criterions for crack tip twinning, grain boundary twinning and inherent twinning, as well as the predicted critical twinning stress. It concludes that alloying with Cr, W and Mo atoms are expected to bring a significant increase in the tendency of the dominant deformation mechanism for the formation of partial dislocations and mechanical twinning of pure Co. The investigation regarding the electronic structure, such as interlayer distance distortion between a faulted and perfect fcc structure, atomic bonding, charge density distributions and density of states (DOS) in the present work can describe why and how alloying atoms change the GSFE values of Co-based alloys. [ABSTRACT FROM AUTHOR]

In the present study the possibility of formation of chromium and vanadium carbide composite coatings on CK45 steel by Thermal Reactive Diffusion method was studied. Two different baths (metal and oxide) and different substrates (CK45 steel and pure iron) were used. Composite carbide coatings including a base phase of chromium carbide (Cr 23 C 6 , Cr 7 C 3 ), and reinforce of vanadium carbide (V 8 C 7 ) were formed on CK45 steel. Also the complex carbide phase of Cr 2 VC 2 has been formed in the carbide coating layer based on XRD results. The ratio of reinforce to the base phase was 0.37 and 0.47, respectively for metal bath and oxide bath. Phase distribution of vanadium carbide in the chromium carbide base phase in metal bath was more homogeneous than in oxide bath. The thickness of the composite carbide coating was 6 μm greater in metal bath than in oxide bath. In addition to carbon, iron diffusion has also occurred from the substrate into the coating. Results indicate that composite chromium and vanadium carbide coatings were successfully formed on CK45 sample in the borax baths consisting of either chromium/vanadium metal powders, or chromium/vanadium oxide powders. [ABSTRACT FROM AUTHOR]

Less mass gain and poorer scale adhesion assessed by the tensile test of the AISI 430 stainless steel exposed to O 2 -40%H 2 O at 800 °C were observed in comparison with the exposure to O 2. The reduced mass gain was partly due to Cr-species volatilisation while the worse scale adhesion related to pores formed at scale/steel interface. The Brouwer diagrams were proposed to help discuss the water vapour effect on altering defect concentrations that could affect the oxidation rate and scale adhesion of the studied steel. • AISI 430 stainless steel was exposed to O 2 -40%H 2 O and O 2 at 800 °C. • The steel oxidised in O 2 -40%H 2 O had less mass gain and poorer scale adhesion. • Cr volatilisation in O 2 -40%H 2 O had significant effect on reducing mass gain. • Pores were observed at the interface between steel and scale formed in O 2 -40%H 2 O. • Brouwer diagrams of Cr, Mn and H interstitials in O 2 -H 2 O were proposed. [ABSTRACT FROM AUTHOR]

CrMoV steel was exposed to 500, 550, and 600 °C for up to 120 h in 0.1 and 10 MPa CO 2. A significant change in carbon deposition content was not observed in the 0.1 MPa CO 2, in contrast to the high carbon content at 550 °C and 10 MPa CO 2. The formation of internal Fe-rich M 3 C carbides and super saturation of steel grains with dissolves carbon at 550 °C but not at 500 and 600 °C may be responsible for this difference. The effect of carbon deposition on the outward Fe diffusion via vacancy or interstitial sites was also discussed. • Effect of temperature (500–600 °C) on carbon depositions within the scale develop on CrMoV steel was investigated. • Carbon contents increased with temperature up to 550 °C and then decreased with temperature in supercritical CO 2. • Formation Fe-rich M 3 C carbides were favored at 550 °C while their formation was delayed at 500 and 600 °C. • It is suggested that the carbon depositions can affect the point defects' contribution to the outward Fe diffusion. • Carbon depositions within the scale consisted of amorphous carbon, graphite, or both. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the correlation between aggressiveness of prostate cancer (PCa) and obesity measuring the periprostatic fat on magnetic resonance imaging (MRI). Materials and Methods: One hundred eighty-four patients who had undergone radical retropubic prostatectomy (RRP) were analyzed retrospectively. The different fat measurements (periprostatic fat area (PFA), the subcutaneous fat thickness, the anterior and posterior abdominal fat thicknesses and anteroposterior diameter) were performed on the slices of MRI and then compared with the clinical and pathologic characteristics. Results: The PFA and ratio showed a statistically significant differences (P = .019 and P = .025, respectively) among three groups, that is to say, more adipose were distributed in periprostatic area of the high risk patients. Seventy-one patients in clinical stage and 82 patients in Gleason score have the significant differences between pre-operation and post-operation values. In the clinical stage, the PFA and ratio showed a statistically significant differences (P = .014 and P = .037, respectively). The difference group had more periprostatic adipose than the other one (65.26 ± 9.03 vs. 64.44 ± 9.62; 87.52 ± 3.97 vs. 87.30 ± 3.96). Nothing but the "PFA" was significantly different between two groups (P = .017). Logistic regression analysis adjusted for age revealed a statistically significant association between the PFA, the Ratio and the risk of having high-risk disease (P = .031 and P = .024, respectively). Conclusion: The periprostatic adiposity not only affects the PCa aggressiveness, but also has effect in accurate assessment of the tumor stage and grade. We should predict the prognosis of patient with RRP by measuring periprostatic adiposity on pre-operative MRI. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the correlation between aggressiveness of prostate cancer (PCa) and obesity measur­ing the periprostatic fat on magnetic resonance imaging (MRI).Materials and Methods: One hundred eighty-four patients who had undergone radical retropubic prosta­tectomy (RRP) were analyzed retrospectively. The different fat measurements (periprostatic fat area (PFA), the subcutaneous fat thickness, the anterior and posterior abdominal fat thicknesses and anteroposterior diameter) were performed on the slices of MRI and then compared with the clinical and pathologic char­acteristics.Results: The PFA and ratio showed a statistically significant differences (P = .019 and P = .025, respec­tively) among three groups, that is to say, more adipose were distributed in periprostatic area of the high risk patients. Seventy-one patients in clinical stage and 82 patients in Gleason score have the significant dif­ferences between pre-operation and post-operation values. In the clinical stage, the PFA and ratio showed a statistically significant differences (P = .014 and P = .037, respectively). The difference group had more periprostatic adipose than the other one (65.26 ± 9.03 vs. 64.44 ± 9.62; 87.52 ± 3.97 vs. 87.30 ± 3.96). Noth­ing but the "PFA" was significantly different between two groups (P = .017). Logistic regression analysis adjusted for age revealed a statistically significant association between the PFA, the Ratio and the risk of having high-risk disease (P = .031 and P = .024, respectively).Conclusion: The periprostatic adiposity not only affects the PCa aggressiveness, but also has effect in accurate assessment of the tumor stage and grade. We should predict the prognosis of patient with RRP by measuring periprostatic adiposity on pre-operative MR. [ABSTRACT FROM AUTHOR]

Background: We sought to analyze the growing worldwide trends of intracranial aneurysm research, investigate China's recent contribution, and compare the contributions of mainland China, Taiwan, and Hong Kong. Methods: Global and China intracranial aneurysm-related publications were retrieved from the Web of Science database from 1991 to 2012. Excel 2007, Matlab, and Thomson Data Analyzer (TDA) software were used to analyze the search results for number of publications, cited frequency, h-index, and organization contributions. Results: 16468 global papers were identified that were cited 273500 times until 2013-08-15. The United States accounted for 31.497% of the articles, 58.64% of the citations, and the highest h-index (127). Japan and Germany followed in frequency. China's articles ranked eighth (third in 2012) in total number, with most of the contributions occurring since 2002 (91.33%). China was at the early stage of the logic growth curve (exponential growth), with the citation frequency and h-index per year increasing. The quality of the publications was low. The main research centers were located in Beijing, Shanghai, Taiwan, and Hong Kong. The main Asian funding body was the National Natural Science Foundation of China. The number of publications and frequency of citations of papers from mainland China was greater than that of Taiwan or Hong Kong. Conclusion: Global intracranial aneurysm research has been developing swiftly since 1991, with the United States making the largest contribution. Research in China started later, in 2002. Since then, China has increased its rate of publication, and became the third largest contributor by 2012. [ABSTRACT FROM AUTHOR]

Abstract: This work used in-situ scanning electron microscopy method to investigate the small fatigue crack behavior of the aluminum alloy 2024 laminated structure produced by ultrasonic consolidation process. The influence of local microstructure on the crack propagation of the laminates after different heat treatments (T4 and T62) has been compared and discussed. It was found that both the precipitations and the interfaces of the layers could retard crack growth and alter the growth direction, and the effect of interfaces was much stronger. Due to the higher ratio of the toughness to bond strength, the barrier effect of the interfaces on impeding the fatigue crack growth in specimens after the T4 heat treatment was more evident. [Copyright &y& Elsevier]

Introduction: To evaluate the effects of the multiple burr hole (MBH) revascularization on ischemic type adult Moyamoya disease (MMD) by computed tomography perfusion (CTP). Methods: Eighty-six ischemic MMD patients received CTP 1 week before and 3 weeks after MBH operation. Fifty-seven patients received it again at 6 month and underwent digital subtraction angiography (DSA) and mRS follow-up. Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP), and relative values of ischemic symptomatic hemispheres were measured. Differences in pre- and post-surgery perfusion CT values were assessed. Results: There were significant differences of CBF, TTP, and relative time to peak (rTTP) in ischemic hemisphere between 1 week before and 3 weeks after surgery, and no significant difference in relative cerebral blood flow (rCBF), CBV, relative cerebral blood volume (rCBV), MTT, relative mean transit time (rMTT). According to whether there was symptom improvement or not on 3 weeks after MBH, the rTTP value was not statistically significant in the patients whose symptoms were not improved at all on 3 weeks after operation. Six-month follow-up showed that CBF, rCBF, and rCBV values were significantly higher than those before operation. Postoperative MTT, TTP, rMTT, and rTTP values were significantly lower than those before operation. Conclusion: CTP is a sensitive method to obtain functional imaging of cerebral microcirculation, which can be a noninvasive assessment of the abnormalities of intracranial arteries and cerebral perfusion changes in MMD before and after surgery. CBF and TTP map, especially the relative values of TTP, seems to have the capability of being quite sensitive to the presence of altered brain perfusion at early time after indirect revascularization. [ABSTRACT FROM AUTHOR]

Purpose: This study is to investigate the value of double contrast-enhanced ultrasonography (DCEU) in assessing microcirculation of colorectal adenocarcinomas and to describe the perfusion features of the tumours. Material and Methods: DCEUS was performed in 42 patients with adenocarcinoma. The time-intensity curve parameters (arrival time (AT), time-to-peak (TTP), peak intensity (PI) and area under the curve (AUC)) within the tumours were extracted. The parameters were compared among the tumours with different CEUS features and stages. Results: The mean values of AT, TTP, PI and AUC of the colorectal adenocarcinomas were 13.68±13.36s, 32.61±19.56s, 19.82±16.54dB and 271.10±159.19dBs, respectively. In the adenocarcinomas with necrosis, the mean values of AUC was significantly lower than that of the adenocarcinomas without (231.10±219.27dBs, 278.10±123.20dBs, p=0.004). In the adenocarcinomas with necrosis, the AUC and PI of the non-necrotic part were significantly higher than that of the necrotic part (p=0.007, 0.0025, respectively). AUC increased progressively in the subgroups of T2, T3 and T4 and the difference of AUC between T2 and T4 subgroup was significant (p=0.008). Conclusions: Double contrast-enhanced ultrasonography is a valuable technique for quantifying tumour vascularity of colorectal adenocarcinomas. AUC was significantly different in the subgroups of different T stage. AUC and PI could reflect the different perfusion status of tumours with or without necrosis. [ABSTRACT FROM AUTHOR]

Objective: To investigate the profile of pelvic crush fractures in earthquake victims on digital radiography (DR) and multidetector computed tomography (MDCT).Materials and Methods: One hundred and sixty-seven consecutive survivors of the 2008 Sichuan earthquake with pelvic crush fractures classified into types according to the Tile classification system, entered our study. One hundred and thirty-nine, and 28 patients underwent DR and MDCT scans, respectively. Data were reviewed retrospectively focusing on anatomical sites, numbers, and classification of pelvic ring fractures.Results: Pelvic fractures occurred in the pubis in 88 patients (52.7%), in other pelvic bones in 32 (19.16%), and in both the pubis and other pelvic bones in 47 (28.14%). Pubic fractures were more common than fractures of other pelvic bones, and involvement of bilateral pubis was more common than that of the left or right pubis (all p < 0.05). As for the numbers of pelvic bones involved, multiple fractures occurred in 48.52% patients (81 out of 167) composed predominantly of fractures of two bones in 58.02% (47 out of 81), and were seen more often in bilateral pubis than in any other pelvic bones (p < 0.05). Regarding classifications of pelvic ring fractures, they were Type A in 31 patients (18.56%); Type B in 72 (43.11%), predominantly Type B2 in 26 (15.58%) and Type B3 in 28 (16.77%); and Type C in 64 (38.32%), predominantly Type C3 in 40 (23.95%).Conclusion: Pelvic crush fractures particularly including multiple pelvic fractures, occurring predominantly in bilateral pubis, and composed of Type C3 followed by Type B3 and Type B2, could be considered to be the profile of pelvic crush fractures in an earthquake. [ABSTRACT FROM AUTHOR]