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Friction spot joining (FSpJ) has been proven to be a highly competitive process for fabricating hybrid joints composed of metal and carbon fibre-reinforced thermoplastic. However, previous research has rarely focused on optimizing joint performance by controlling thermal conduction through modifying tool structures. This study systematically explores the effect of the recessed tool shoulder geometry on mechanical strength of 6061-T6 Al alloy and carbon fibre-reinforced polyamide-6 (CF/PA6) pinless-FSpJ joint. An experimentally validated three-dimensional (3D) finite element model was built to investigate the heat generation and thermal conduction. Results show that the recessed tools with different external diameters achieve higher average interface strength in lap joints compared to flat shoulder tools. Under fixed plunge depth conditions, increasing the depth of the recessed area results in a lower rate of temperature rise and a more uniform temperature distribution during heating stage. As a result, the duration of resin decomposition in the molten state is further reduced, but the time in a single molten state is extended. This benefits the wetting process of molten resin on the silanized Al surface and subsequent chemical reaction with the silane film, while alleviating decomposition defects to a certain extent. The reduction in residual tension stress at the center of Al upper surface indirectly indicates the improving effect of increased recessed tool depth on the stress state of the joint.

The effect of Li on the microstructure and corrosion behavior of extruded Mg-xLi-3Al-0.4Ca (x = 4,5,6,7) alloys were investigated by hydrogen evolution, potentiodynamic polarization measurement and electrochemical impedance spectroscopy measurement. The single-phase 4Li alloy with the largest α-Mg grain size and the strongest basal texture intensity exhibits the best corrosion resistance in 3.5 wt% NaCl solution. The duplex 6Li and 7Li alloys contain a protective LiOH film in the corrosion products, giving them better corrosion resistance than 5Li alloy. This study provides a new insight for the design and preparation of Mg–Li alloys with high corrosion resistance.

Coaxial one-side resistance welding (COS-RSW) is an advanced joining technology for the metal-plastic hybrid structure, which has great application potential in the lightweight design of body-in-white. In the present research, the Al5052-CFRP cross-lap joints were fabricated by COS-RSW with different welding conditions. The author-developed finite element (FE) code JWRIAN-RSW was employed to reproduce the multi-physics coupled phenomena of COS-RSW and predict thermal history. The influence of welding current and welding time on molten zone generation and joining strength was discussed in detail. The results showed that the developed FE model can predict temperature distribution and variation effectively, which were verified by the bonding zone observation and infrared thermal image measurement. Both welding current and welding time had a significant contribution to the Joule heat generation. While their influence on the molten zone growth during heating and cooling stage was distinct. The maximum joining strength of COS-RSW cross-lap joints can reach about 1380 N. The static tensile strength was improved significantly when the maximum interface temperature exceeded 340 °C and the failure mode altered into staged fracture. The strength degradation induced by significant CFRP decomposition was appeared when the predicted interface temperature reached 410 °C. For the COS-RSW joint of Al5052 and CFRP, it was better to improve the joining strength using longer welding time rather than higher welding current, which led to sufficient heat generation, persistent thermal conduction and elongated melting duration for sound joining.

Carbon fiber-reinforced thermoplastics (CFRTPs) and lightweight metals are widely used in multi-material structures owing to their high strength and excellent corrosion resistance, thus stimulating research on various heat-assisted techniques to join them. Currently, the isothermal-pressing process has been developed to realize sound interface joining between CFRTP and Al alloy under relatively uniform thermal conditions. However, a quantitative investigation of the interaction between thermal conditions, chemistry reactions, and joining strength is still lacking. This current investigation analyzed chemical reaction state and resultant bonded strength of isothermal-pressing joined interface of silanized 5052 Al alloy and carbon fiber-reinforced polyamide-6 (CF/PA6) under various thermal conditions. X-ray photoelectron spectroscopy and Raman scattering analysis showed the increasing consumption of epoxy groups on silanized 5052 Al alloy side with the increase in joining temperature and residence time. This suggested higher temperatures and sufficient high-temperature duration times could efficiently promote the interface chemical reaction, increasing interface bonding strength. As the joining temperature or residence time increased, the fracture location gradually shifted from the silane coupling layer/re-solidified resin interface to the re-solidified resin close to interface, and even it directly passed through CF/PA6 along the thickness direction. Under the current adopted conditions, a critical high-temperature duration time of ∼6.0 s at least was recommended by optimizing the joining time to achieve high-strength joining between 5052 Al alloy and CF/PA6. The findings will guide optimizing the joining conditions in heat-assisted joining processes of Al/CFRTP hybrid structures.

Background: The prognostic value of follow-up cardiovascular magnetic resonance (CMR) in dilated cardiomyopathy (DCM) patients is unclear. We aimed to investigate the prognostic value of cardiac function, structure, and tissue characteristics at mid-term CMR follow-up. Methods: The study population was a prospectively enrolled cohort of DCM patients who underwent guideline-directed medical therapy with baseline and follow-up CMR, which included measurement of biventricular volume and ejection fraction, late gadolinium enhancement, native T1, native T2, and extracellular volume. During follow-up, major adverse cardiac events (MACE) were defined as a composite endpoint of cardiovascular death, heart transplantation, and heart-failure readmission. Results: Among 235 DCM patients (median CMR interval: 15.3 months; interquartile range: 12.5–19.2 months), 54 (23.0%) experienced MACE during follow-up (median: 31.2 months; interquartile range: 20.8–50.0 months). In multivariable Cox regression, follow-up CMR models showed significantly superior predictive value than baseline CMR models. Stepwise multivariate Cox regression showed that follow-up left ventricular ejection fraction (LVEF; hazard ratio [HR], 0.93; 95% confidence interval [CI], 0.91–0.96; p 1273 ms or LVEF 15%). Conclusions: Follow-up CMR provided better risk stratification than baseline CMR. Improvements in the LVEF and T1 mapping are associated with a lower risk of MACE.

We undertook a survey among epileptologists in China to explore their attitudes toward physical exercise and sports for persons with epilepsy (PWEs). A total of 288 epileptologists participated. Most recognized the potential benefits of physical exercise and sports for PWEs, including improved cognitive function (74.6 %), alleviation of mental disorders (73.2 %), and enhanced quality of life (83.8 %). Epileptologists overwhelmingly agreed on the importance of discussing and encouraging physical exercise and sports for PWEs (97.4 % and 95.2 %, respectively). Before engagement in physical exercise and sports, most epileptologists considered that the duration of seizure-free status could be shorter if the seizures were typically focal, non-motor, or without impaired awareness (p

Linear friction welding (LFW) was performed on face-centered cubic materials, that is, Al alloys (AA1050 and AA5052) with different stacking fault energies (SFEs). The pressure was controlled during the LFW to clarify the effects of temperature, strain, and strain rate on microstructural evolution and dynamic recrystallization (DRX) mechanism. The microstructural evolution during DRX was mainly dependent on the temperature. The grain structures and textural evolution at high temperatures were governed by a continuous DRX, whereas those at low temperatures were primarily controlled by a discontinuous DRX. Various parameters determined the grain structure and textural evolution in different regimes. The evolution of grain structures and texture was dominated by strains and strain rates at temperatures above 0.5Tm (Tm: melting temperature) and by the SFE at temperatures below 0.5Tm. The Zener–Hollomon parameters of the Al alloy joints were investigated. It was found that the slope in AA5052 is larger than that in AA1050 during LFW. At a lower Z value, the grain diameter of the AA5052 joints was larger than that of the AA1050 joints, presumably because of the lower strain rate. Contrastingly, at a higher Z value, the grain diameter of the AA5052 joints was smaller than that of the AA1050 joints, even though the strain rates of the AA5052 joints were considerably lower than those of the AA1050 joints. These results were mainly attributed to the lower SFE of AA5052, which promoted DRX and grain refinement during the LFW. This report reveals the effects of SFE, temperature, strain, and strain rate on the DRX-induced microstructural evolutions during severe plastic deformation.

Abstract Background The value of right atrial (RA) function in cardiovascular diseases is currently limited. This study was to explore the prognostic value of RA strain derived from fast long axis method by cardiovascular magnetic resonance (CMR) in patients with non-ischemic dilated cardiomyopathy (DCM). Methods We prospectively enrolled patients with DCM who underwent CMR from June 2012 to March 2019 and 120 age- and sex-matched healthy subjects. Fast long-axis strain method was performed to assess the RA phasic function including RA reservoir strain, conduit strain, and booster strain. The predefined primary endpoint was all-cause mortality. The composite heart failure (HF) endpoint included HF death, HF readmission, and heart transplantation. Cox regression analysis and Kaplan–Meier survival curve were performed to describe the association between RA strain and outcomes. Results A total of 624 patients (444 men, mean 48 years) were studied. After a median follow-up of 32.5 months, 116 patients (18.6%) experienced all-cause mortality and 205 patients (32.9%) reached composite HF endpoint. RA function was impaired in DCM patients compared with healthy subjects (all P

The reaction between solid Fe and liquid Al occupies the important position due to its wide application in industrial processes. However, it is still unclear now which intermetallic compounds will form and the formation mechanism of Fe–Al intermetallic phases. In present work, the Fe–Al solid-liquid reaction by using iron wire as Fe resource is traced by in-situ synchrotron powder X-ray-diffraction. With Fe4Al13 as the dominant phase, two intermetallic phases named Fe4Al13 and Fe2Al5 are found. This phenomenon is different with the result obtained from the diffusion couple of Fe block and melt Al. Thermodynamic calculation and molecular dynamics simulation are performed to verify the underlying mechanism. Related events such as interfacial diffusion and nucleation driving force are analyzed and discussed.

The microstructure evolution of the AA5052-H34 joint and AA5083-O joint fabricated by linear friction welding (LFW) was evaluated in a wide range of interfacial temperatures, i.e., applied pressures. The grain refinement of Al alloys with high stacking fault energy was found to be mainly dominated by discontinuous dynamic recrystallization (DDRX) at low temperatures. While, it was clear that grain refinement at high temperatures was dominated by continuous dynamic recrystallization (CDRX). In the joint of work hardened AA5052-H34 fabricated at low applied pressure of 50 MPa (above the 0.5 Tm), the annealing effect was more significant than the grain-boundary strengthening effect at the WC, leading to the softening. However, the increased applied pressure to 100 MPa resulted in the flat hardness distribution due to the increased strengthening by grain refinement. On the other hand, in the joint of annealed AA5083-O, the flat hardness was obtained at the lower pressure of 50 MPa, because both the low angle grain boundary length per unit area and dislocation density at the WC was almost equivalent to that of base material.

Obstructive sleep apnea-hypopnea (OSAH) is correlated with an increased incidence of lung cancer. In our study, we explored the functional roles of microRNAs (miRNAs) in lung cancer patients that were complicated with OSAH involving the deubiquitination enzyme. The miR-320b expression pattern in lung cancer tissues and cells was determined. The interactions between ubiquitin-specific peptidase 37 (USP37) and miR-320b were evaluated by a dual-luciferase reporter gene assay, whereas USP37 and Cdc10-dependent transcript 1 (CDT1) was assessed by co-immunoprecipitation and immunofluorescence. After the induction of intermittent hypoxia (IH), a gain-of function approach was performed to investigate roles of miR-320b, USP37, and CDT1 in lung cancer cell proliferation and invasion. In addition, nude mouse xenograft models were used to study their effects on tumor growth in vivo. miR-320b was poorly expressed in lung cancer patients with OSAH. IH treatment downregulated the expression of miR-320b but promoted the proliferation and invasion capabilities of lung cancer cells, both of which were suppressed by the overexpression of miR-320b through decreasing USP37. USP37 interacted with and deubiquitinated CDT1 to protect it from proteasomal degradation. Our study uncovered that IH-induced downregulation of miR-320b promoted the tumorigenesis of lung cancer by the USP37-mediated deubiquitination of CDT1.

Abstract Background The prognostic value of left atrial (LA) size and function in hypertrophic cardiomyopathy (HCM) is well recognized, but LA function is difficult to routinely analyze. Fast LA long-axis strain (LA-LAS) analysis is a novel technique to assess LA function on cine cardiovascular magnetic resonance (CMR). We aimed to assess the association between fast LA-LAS and adverse clinical outcomes in patients with HCM. Methods 359 HCM patients and 100 healthy controls underwent routine CMR imaging. Fast LA-LAS was analyzed by automatically tracking the length between the midpoint of posterior LA wall and the left atrioventricular junction based on standard 2- and 4-chamber balanced steady-state free precession cine-CMR. Three strain parameters including reservoir strain (εs), conduit strain (εe), and active strain (εa) were assessed. The endpoint was set as composite adverse events including cardiovascular death, resuscitated cardiac arrest, sudden cardiac death aborted by appropriate implantable cardioverter-defibrillator discharge, and hospital admission related to heart failure. Results During an average follow-up of 40.9 months, 59 patients (19.7%) reached endpoints. LA strains were correlated with LA diameter, LA volume index (LAVI) and LA empty fraction (LAEF) (all p

Abstract Background Idiopathic inflammatory myopathy (IIM) manifest as systematic muscle involvement. Multiparametric cardiovascular magnetic resonance (CMR) could be a useful technique to detect systemic involvement and disease progression in IIM patients. This study aimed to describe the tissue characteristics and dynamic changes in myocardial and skeletal muscles after treatment in IIM patients. Methods Forty-four consecutively recruited IIM patients (49.0 ± 12.0 years; 22 males) underwent 3 T CMR at first diagnosis, and 28 patients underwent follow-up scan after receiving standard treatment for more than 1 year. Thirty age- and sex-matched healthy subjects served as controls. The CMR protocol included: cines, T2-weighted (T2w), late gadolinium enhancement (LGE), T1 and T2 mapping, and extracellular volume (ECV) evaluated for the myocardium, and T1 and T2 mapping and ECV evaluated for skeletal muscles. Correlations between laboratory biomarkers and myocardial and skeletal tissue characteristics were analyzed. Comparisons between baseline and follow-up scans were performed using paired t-tests. Results At baseline, IIM patients showed significantly decreased hematocrit, higher left ventricular (LV) mass index, right ventricular (RV) volume index, myocardial and skeletal native T1, T2 mapping, and ECV than healthy controls. Significant correlations were found among myocardial native T1, T2 mapping, and ECV values and N-terminal pro b-type natriuretic peptide (NT-proBNP) levels, and significant correlations between skeletal T2 mapping and inflammatory biomarkers in IIM patients. During the follow-up, 28 patients underwent repeated CMR scan (median interval, 14.5 months, interquartile range: 13.2–15.5 months). Significant relief from clinical symptoms and decreased inflammatory biomarkers levels were observed. Significant reduction in myocardial native T1, T2, ECV, and skeletal native T1, T2, and ECV were observed during the follow-up assessment. Conclusions Both myocardial and skeletal muscles in newly diagnosed IIM patients show distinct characteristics on multiparametric CMR. In addition, significant changes were observed in patients showing clinical remission after effective treatment, which suggests that quantitative T1, T2, and ECV techniques may have potential clinical value in IIM patients.

Background: Total lesion glycolysis has been reported to be a satisfactory predictor of survival in patients with locally advanced esophageal cancer (EC). The aim of the present study is to investigate the function of long intergenic non-protein coding RNA 184 (LINC00184) on the EC cell glycolysis and mitochondrial oxidative phosphorylation (OXPHOS). Methods: The expression of LINC00184 was determined to be highly expressed and PTEN was poorly expressed in EC tissues and cells by RT-qPCR. In order to evaluate the effects of LINC00184 on cellular process in vitro and in vivo, gain- and loss-of-function approaches were performed to alter the expression of LINC00184 and PTEN in EC cells. Results: Silencing of LINC00184 was observed to inhibit the proliferation, migration, invasion, colony formation, and glycolysis of EC cells and tumour growth, while the mitochondrial OXPHOS was restored. By recruiting DNMT1, LINC00184 enhanced the promoter methylation of PTEN. Inhibition of PTEN promoter methylation suppressed EC glycolysis, whereas, improved mitochondrial OXPHOS. Mechanically, LINC00184 modulated glycolysis and mitochondrial OXPHOS in EC cells through induction of the Akt phosphorylation. After blockage of Akt signaling pathway by an Akt inhibitor, LY294002, the regulatory effects of LINC00184 on the glycolysis and mitochondrial OXPHOS of EC cells were reversed. Conclusion: Taken together, the LINC00184/PTEN/Akt axis mediates glycolysis and mitochondrial OXPHOS in EC cells. This study highlighted a potential intervention target for treating EC. Keywords: Esophageal cancer, Long intergenic non-protein coding RNA 184, Phosphatase and tensin homolog, Methylation, Glycolysis, Mitochondrial oxidative phosphorylation