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Left ventricular non-compaction (LVNC) is a complex clinical condition with several diagnostic criteria but no diagnostic gold standard. We aimed to evaluate our thresholding technique in a group of patients with LVNC and assess the risk of major adverse cardiovascular and cerebrovascular events (MACCE). We retrospectively analyzed cardiac magnetic resonance (CMR) scans of patients with Petersen criteria LVNC and quantified noncompacted myocardial mass. We assessed the association of noncompacted myocardial mass, CMR derived LV volumetric parameters and late gadolinium enhancement (LGE) to MACCE including cardiac death, cardiac transplantation, sustained ventricular tachycardia/ventricular fibrillation (VT/VF) and ischemic stroke. Patients with known genetic mutations and cardiovascular disease were excluded. 98 patients with LVNC were included (55 males,56.7%); 17(17.3%) patients had impaired LV function and five (5.1%) had LGE. Patients with impaired LV function had more end-systolic noncompacted mass (61.9 g±22.4 vs. 38.1 g±15.8, p < 0.001) and larger end-systolic noncompacted to total myocardial mass (44%±9 vs. 36%±12, p = 0.003). At 78 months follow-up [interquartile range(IQR) 66–90], MACCE occurred in 11(11.3%) patients; nine(81.8%) had impaired LV function and two(18.2%) had LGE. Impaired LV function and LV LGE were predictors of MACCE (HR = 35.6, 95% CI = 7.65–165.21, p < 0.001 and HR = 16.2, 95% CI = 4.54–57.84, p < 0.001) whereas noncompacted mass were not. Noncompacted mass was not an independent predictor of major adverse events but in patients with impaired LV function and/or LV LGE, the risk of MACCE was high. These results highlight the importance of including LV volumetrics and scar in the assessment of patients with LV noncompaction. • In patients with hyper-trabeculation fulfilling the Petersen criteria for left ventricular noncompaction (LVNC). • Noncompacted mass was not an independent predictor of adverse events. • Patients with impaired LV function and/or LGE had worse clinical outcomes. • LVNC criteria should include these parameters to improve clinical accuracy. [ABSTRACT FROM AUTHOR]

Oxy-fuel combustion of heavy oil can be applied to oil field steam injection boilers, allowing the utilization of both heavy oil and CO 2 resources. This paper studied the local distribution characteristics of OH on oxy-fuel combustion of heavy oil during the ignition and stable combustion processes. During the ignition process, we observed the generation and evolution of fire kernel, and got the flame propagation velocity. During the stable combustion process, the results showed that the OH distribution and its relative signal intensity were influenced by the oxygen concentration, excess air coefficient, gas flow, reaction atmosphere, oil mist scattering, incident laser energy and laser sheet position. In the same reaction atmosphere, the ranges of OH dense distribution and the high temperature area increased as O 2 concentration increased. In the same O 2 concentration, both the ranges of OH dense distribution and the high temperature area in O 2 /N 2 were larger than that in O 2 /CO 2. In 29% O 2 /71% CO 2 , the flame shape was similar to combust in air, while the OH relative signal intensity and its volatility were much larger than that in air. In the same combustion condition, the location of high concentration of OH relative concentration field lagged behind the high temperature area. The results further reveal the differences between the conventional and oxy-fuel combustion. • OH distribution relative signal intensity was influenced by the oxygen concentration, excess air coefficient, gas flow, reaction atmosphere and so on. • In the same reaction atmosphere, the ranges of OH dense distribution and the high temperature area increased as O 2 concentration increased. • In the same O 2 concentration, both the ranges of OH dense distribution and the high temperature area in O 2 /N 2 were larger than those in O 2 /CO 2. • In 29% O 2 /71% CO 2 , the flame shape was similar to combusted in air, but the OH relative signal intensity was much larger than that in air. [ABSTRACT FROM AUTHOR]

Introduction: The difficulty of predicting the efficacy of somatostatin analogs (SSA) is not fully resolved. Here, we quantitatively evaluated the predictive value of relative signal intensity (rSI) on T1- and T2-weighted magnetic resonance imaging (MRI) for the short-term efficacy (3 months) of SSA therapy in patients with active acromegaly and assessed the correlation between MRI rSI and expression of somatostatin receptors (SSTR). Methods: This was a retrospective review of prospectively recorded data. Ninety-two newly diagnosed patients (37 males and 55 females) with active acromegaly were recruited. All patients were treated with pre-surgical SSA, followed by reassessment and transspenoidal surgery. rSI values were generated by calculating the ratio of SI in the tumor to the SI of normal frontal white matter. The Youden indices were calculated to determine the optimal cutoff of rSI to determine the efficacy of SSA. The correlation between rSI and expression of SSTR2/5 was analyzed by the Spearman rank correlation coefficient. Results: T2 rSI was strongly correlated with biochemical sensitivity to SSA. The cutoff value of T2 rSI to distinguish biochemical sensitivity was 1.205, with a positive predictive value (PPV) of 81.5 % and a negative predictive value (NPV) of 77.3 %. No correlation was found between MRI and tumor size sensitivity. Moreover, T2 rSI was negatively correlated with the expression of SSTR5. Conclusion: T2 rSI correlates with the expression of SSTR5 and quantitatively predicts the biochemical efficacy of SSA in acromegaly. [ABSTRACT FROM AUTHOR]

Previous studies have indicated that the temporal change of relative diffusion weighted imaging (rDWI) signal intensity may help to determine the onset time of a stroke. Furthermore, several studies have indicated that high b value DWI offered improved detection rates for hyper-acute ischemic lesions compared with standard b value DWI. However, the temporal changes of the rDWI on high b value DWI remain unclear. Therefore, based on our embolic canine stroke model, we evaluated the temporal evolution of rDWI on high b value DWI, and further compared its diagnostic value in predicting the onset time of ischemic stroke with rDWI on standard b value DWI. Twelve canine MCAO models were established, and DWI was performed at 1, 2, 3, 4, 5 and 6 h after MCAO, with 3 b values of 1,000, 2,000 and 3,000. High b value DWI detected all ischemic lesions after 1 h, while standard b value did not detect the ischemic lesions in one dog at 1 h. With all three of the tested b values, rDWIs increased continuously within 6 h, while relative apparent diffusion coefficient (rADC) values rapidly decreased in 1 h, then became relatively stable. The area under the curve values for rDWI with b value of 1,000, 2,000 and 3,000, in predicting ischemic lesions within 3 h were 0.897, 0.929 and 0.938, while for rADC were 0.645, 0.583 and 0.599, respectively. Therefore, the results indicated that the rDWI was helpful in aging hyper-acute ischemic stroke, while rADC appeared not to be. High b value DWI had a higher detection rate for ischemic lesions and better predictive efficacy in determining the onset time of hyper-acute stroke. [ABSTRACT FROM AUTHOR]

In acute stroke magnetic resonance imaging, many attempts have been made to identify the onset time of ischemic events using the simply quantitative judgment of relative signal intensity (rSI) from various MR images. However, no uniform opinion has been achieved broadly till now. The controversy might derive from the potential patients' selection bias of clinical retrospective study, the discrepant MR parameters, and the various sample sizes among different studies. Thus, we evaluated the temporal change of the relative DWI signal intensity (rDWI), relative ADC value (rADC), relative FLAIR signal intensity (rFLAIR), and relative T2 signal intensity (rT2), and further compare their diagnostic value in identifying the hyperacute lesions based on our embolic canine model with clear onset time. Twenty ischemic models were successfully established. All rSI values were linearly correlated to time with significance until 24 h after model establishment ( P < 0.05). Paired comparison of ROC curves showed that significant difference was found between rADC and other three rSIs ( P < 0.0001). However, no significant difference was found among rDWI, rT2 and rFLAIR. Our results indicated that rDWI, rFLAIR and rT2 may be helpful to predict the onset time of ischemic events with the similar diagnostic value. However, the rADC does not have comparable predictive value in our embolic canine model. [ABSTRACT FROM AUTHOR]

Previous studies have indicated that the temporal change of relative diffusion weighted imaging (rDWI) signal intensity may help to determine the onset time of a stroke. Furthermore, several studies have indicated that high b value DWI offered improved detection rates for hyper-acute ischemic lesions compared with standard b value DWI. However, the temporal changes of the rDWI on high b value DWI remain unclear. Therefore, based on our embolic canine stroke model, we evaluated the temporal evolution of rDWI on high b value DWI, and further compared its diagnostic value in predicting the onset time of ischemic stroke with rDWI on standard b value DWI. Twelve canine MCAO models were established, and DWI was performed at 1, 2, 3, 4, 5 and 6 h after MCAO, with 3 b values of 1,000, 2,000 and 3,000. High b value DWI detected all ischemic lesions after 1 h, while standard b value did not detect the ischemic lesions in one dog at 1 h. With all three of the tested b values, rDWIs increased continuously within 6 h, while relative apparent diffusion coefficient (rADC) values rapidly decreased in 1 h, then became relatively stable. The area under the curve values for rDWI with b value of 1,000, 2,000 and 3,000, in predicting ischemic lesions within 3 h were 0.897, 0.929 and 0.938, while for rADC were 0.645, 0.583 and 0.599, respectively. Therefore, the results indicated that the rDWI was helpful in aging hyper-acute ischemic stroke, while rADC appeared not to be. High b value DWI had a higher detection rate for ischemic lesions and better predictive efficacy in determining the onset time of hyper-acute stroke.