Clinical Significance of Angiographically Detectable Neovascularity in Patients with Cardiac Myxoma

Background: Myxomas are the most common primary cardiac tumors. Angiographically detectable neovascularity (ADN) of myxoma is increasingly being reported as a result of the use of coronary angiography (CAG) to detect coronary artery disease. However, the clinical significance of these findings is not fully understood. Methods: We enrolled 59 patients with cardiac myxoma who also underwent CAG between January 2013 and October 2018. Patients were followed up for a mean of 28.9 months (range 1–69 months). The clinical features, echocardiography measurements, pathological examination findings, CAG results, and outcomes during follow-up were compared between patients with ADN and patients without ADN. Results: ADN was found in 25 patients (42.4%). The arteries feeding the ADN included the right coronary artery ( n=15), the left circumflex coronary artery ( n=7), and both arteries ( n=3). The patients with ADN had a higher proportion of eosinophils (3.2% vs. 2.2%, P=0.03) and higher low-density lipoprotein cholesterol level (2.7 mmol/L vs. 2.2 mmol/L, P=0.02). Myxoma pedicles were more likely to be located in the interatrial septum in patients with ADN (96% vs. 73.5%, P=0.02). No significant correlation was observed between the groups in clinical manifestations, atrial arrhythmia, myxoma size, cardiac chamber size, left ventricular ejection fraction, and the prevalence of complication with coronary artery disease [16% in the ADN group ( n=4) vs. 20.6% in the non-ADN group ( n=7), P=0.66]. However, patients with ADN tended to have a lower incidence of major adverse cardiac and cerebrovascular events on long-term follow-up (0% vs. 14.7%, P=0.07). Conclusion: CAG-detected ADN in patients with cardiac myxoma is associated with a borderline lower rate of major adverse cardiac and cerebrovascular events. </p

Using artificial intelligence to improve identification of nanofluid gas–liquid two-phase flow pattern in mini-channel

This work combines fuzzy logic and a support vector machine (SVM) with a principal component analysis (PCA) to create an artificial-intelligence system that identifies nanofluid gas-liquid two-phase flow states in a vertical mini-channel. Flow-pattern recognition requires finding the operational details of the process and doing computer simulations and image processing can be used to automate the description of flow patterns in nanofluid gas-liquid two-phase flow. This work uses fuzzy logic and a SVM with PCA to improve the accuracy with which the flow pattern of a nanofluid gas-liquid two-phase flow is identified. To acquire images of nanofluid gas-liquid two-phase flow patterns of flow boiling, a high-speed digital camera was used to record four different types of flow-pattern images, namely annular flow, bubbly flow, churn flow, and slug flow. The textural features extracted by processing the images of nanofluid gas–liquid two-phase flow patterns are used as inputs to various identification schemes such as fuzzy logic, SVM, and SVM with PCA to identify the type of flow pattern. The results indicate that the SVM with reduced characteristics of PCA provides the best identification accuracy and requires less calculation time than the other two schemes. The data reported herein should be very useful for the design and operation of industrial applications

A study on the thermal conductivity of proton irradiated CVD-SiC and sintered SiC, measured using a modified laser flash method with multi-step machining

CVD-SiC and sintered SiC (SPS-SiC) were proton irradiated at 340 ̊C receiving different levels of damage (0.05–0.25 dpa). A novel multi-step machining and measurement method using laser flash analysis (LFA) was developed to derive the thermal conductivity of the irradiated layer (∼46 µm). Before irradiation, the thermal conductivity of SPS-SiC was much lower than CVD-SiC, primarily due to its higher intrinsic defect concentration and smaller grain size which provide a greater density of barriers to phonon transmission. Following irradiation, major thermal conductivity degradation (∼90%) was found to occur to both types of SiC after only a low dose (∼0.1 dpa), with both saturating at a similarly low value (a few W/K⋅m), as the thermal resistivity due to the presence of high density of grain boundaries became less important. Thermal conductivity degradation after irradiation was primarily caused by point defects in both types of SiC, as reflected by Raman spectra

A study on the thermal conductivity of proton irradiated CVD-SiC and sintered SiC, measured using a modified laser flash method with multi-step machining

CVD-SiC and sintered SiC (SPS-SiC) were proton irradiated at 340 ̊C receiving different levels of damage (0.05–0.25 dpa). A novel multi-step machining and measurement method using laser flash analysis (LFA) was developed to derive the thermal conductivity of the irradiated layer (∼46 µm). Before irradiation, the thermal conductivity of SPS-SiC was much lower than CVD-SiC, primarily due to its higher intrinsic defect concentration and smaller grain size which provide a greater density of barriers to phonon transmission. Following irradiation, major thermal conductivity degradation (∼90%) was found to occur to both types of SiC after only a low dose (∼0.1 dpa), with both saturating at a similarly low value (a few W/K⋅m), as the thermal resistivity due to the presence of high density of grain boundaries became less important. Thermal conductivity degradation after irradiation was primarily caused by point defects in both types of SiC, as reflected by Raman spectra

An Aptamer-Array-Based Sample-to-Answer Biosensor for Ochratoxin A Detection via Fluorescence Resonance Energy Transfer

Food toxins are a hidden threat that can cause cancer and tremendously impact human health. Therefore, the detection of food toxins in a timely manner with high sensitivity is of paramount importance for public health and food safety. However, the current detection methods are relatively time-consuming and not practical for field tests. In the present work, we developed a novel aptamer-chip-based sample-to-answer biosensor (ACSB) for ochratoxin A (OTA) detection via fluorescence resonance energy transfer (FRET). In this system, a cyanine 3 (Cy3)-labeled OTA-specific biotinylated aptamer was immobilized on an epoxy-coated chip via streptavidin-biotin binding. A complementary DNA strand to OTA aptamer at the 3′-end was labeled with a black hole quencher 2 (BHQ2) to quench Cy3 fluorescence when in proximity. In the presence of OTA, the Cy3-labeled OTA aptamer bound specifically to OTA and led to the physical separation of Cy3 and BHQ2, which resulted in an increase of fluorescence signal. The limit of detection (LOD) of this ACSB for OTA was 0.005 ng/mL with a linearity range of 0.01–10 ng/mL. The cross-reactivity of ACSB against other mycotoxins, ochratoxin B (OTB), aflatoxin B1 (AFB1), zearalenone (ZEA), or deoxynilvalenol (DON), was less than 0.01%. In addition, this system could accurately detect OTA in rice samples spiked with OTA, and the mean recovery rate of the spiked-in OTA reached 91%, with a coefficient of variation (CV) of 8.57–9.89%. Collectively, the ACSB may represent a rapid, accurate, and easy-to-use platform for OTA detection with high sensitivity and specificity

High Interfacial Shear Strength and High Tensile Strength in Heterocyclic Aramid Fibers with Improved Interchain Interaction

As a typical kind of high-performance fibers, heterocyclic aramid fibers are widely used to reinforce resins to prepare advanced lightweight composites with high mechanical performances. However, their poor interfacial shear strength limits the combination with resins and leads to undesirable interfacial strength of composites. Thus, heterocyclic aramid fibers with high interfacial shear strength and high tensile strength are highly desired. Herein, heterocyclic aramid fibers with a high interfacial shear strength of 40.04 +/- 2.41 MPa and a high tensile strength of 5.08 +/- 0.24 GPa are reported, in which the nitrile-modified poly-(benzimidazole-terephthalamide) polymer chains are crosslinked by azide-functionalized graphene oxide nanosheets. The improved interchain interaction can conquer the splitting of nanofibrils and strengthen the skin-core layer of heterocyclic aramid fibers, while the graphene oxide can induce an ordered arrangement of polymer chains to improve the crystallinity and orientation degree of fibers. These two effects account for the high interfacial shear strength and high tensile strength of heterocyclic aramid fibers. These findings have provided a strategy to efficiently enhance the interfacial shear strength as well as the tensile strength of high-performance fibers. The small addition of GO-N3 can not only improve the interchain interaction to conquer the splitting of nanofibrils and strengthen the skin-core layer of fibers, but also improve the crystallinity and orientation degree of GO-N3/PBIA-CN fibers, leading to the preparation of GO-N3/PBIA-CN fibers with high interfacial shear strength and high tensile strength.imag

Holey reduced graphene oxide scaffolded heterocyclic aramid fibers with enhanced mechanical performance

Poly(p-phenylene-benzimidazole-terephthalamide) (PBIA) fibers, a kind of heterocyclic aramid fibers, possess extraordinary mechanical properties and advanced applications in aerospace, military protection, and other civilian areas. However, harsh application scenarios are putting forward even stringent requirements for the mechanical performances and environmental compatibility of PBIA fibers. Strengthening lateral interactions between polymer chains are approachable methods but ongoing challenges to obtain PBIA fibers with high-performance. This work develops a novel holey reduced-graphene-oxide (HrGO)/PBIA composite fiber with a scaffolded structure, in which the HrGO plays a role of clamp to effectively band plentiful PBIA chains through the in-plane holes. A small amount of HrGO (0.075 wt%) is able to improve the tensile strength and Young's modulus of HrGO/PBIA fibers by 11.5% and 8.3%, respectively. The small amount of well dispersed HrGO improves the crystallinity and serves as the topological constraint that enhances the lateral interaction of the PBIA chains, which is unveiled by the wide-angle X-ray scattering and the coarse-grained molecular dynamics simulations. In addition, the favorable compatibility of HrGO/PBIA fibers in complex application scenarios is demonstrated by the dynamic and cyclic-loading measurements.Submitted/Accepted versionThis work was financially supported by the Ministry of Science and Technology of China (2016YFA0200100 and 2018YFA0703502), the National Natural Science Foundation of China (Grant Nos. 52021006, 51720105003, 21790052, and 21974004), the Strategic Priority Research Program of CAS (XDB36030100), and the Beijing National Laboratory for Molecular Sciences (BNLMS-CXTD-202001)