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High-strength, lightweight, ultrathin, and flexible electromagnetic interference (EMI) shielding materials with a high shielding effectiveness (SE) are essential for modern integrated electronics. Herein, cellulose nanofibrils (CNFs) are employed to homogeneously disperse graphene nanoplates (GNPs) into an aramid nanofiber (ANF) network and silver nanowire (AgNW) network, respectively, producing high-performance nanopapers. These nanopapers, featuring nacre-mimetic microstructures and layered architectures, exhibited high tensile strength (601.11 MPa) and good toughness (103.56 MJ m-3) with a thickness of only 24.58 µm. Their specific tensile strength reaches 447.59 MPa·g-1·cm3, which is 1.74 times that of titanium alloys (257 MPa·g-1·cm3). The AgNW/GNP composite conductive layers exhibit an electrical conductivity of 12010.00 S cm-1, providing the nanopapers with great EMI shielding performance, achieving an EMI SE of 63.87 dB and an EMI SE/t of 25978.80 dB cm-1. The nanopapers also show reliable durability, retaining a tensile strength of 500.96 MPa and an EMI SE of 57.59 dB after 120,000 folding cycles. Additionally, they have a good electrical heating performance with a fast response time, low driving voltage, effective deicing capability, and reliable heating capacity in water. This work presents a strategy to develop a high-performance nanopaper, showing great potential for applications in electromagnetic compatibility, national defense, smart electronics, and human health.

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Background: Delirium is a common postoperative complication of acute type an aortic dissection, which is a serious threat to the patient's life after operation. However, there are many risk factors for delirium and there are different conclusions. The aim of this study was to systematically analyze the risk factors for postoperative delirium in patients with acute type a aortic dissection by means of meta-analysis. Methods: Literature related to the risk factors of postoperative delirium in patients with acute type A aortic dissection was searched via the China National Knowledge Infrastructure (CNKI), cqvip.com (VIP), WanFang, PubMed, Willey Library, Embase, and Web of Science databases. Two persons independently conducted literature screening, data extraction and literature quality evaluation according to the inclusion and exclusion criteria. The quality of literature was evaluated with Newcastle-Ottawa Scale (NOS). R 4.2.1 was used to compare the risk factors for meta-analysis. Results: After screening, 12 articles were included with a total of 2,511 cases, and 4 articles were at medium risk of bias and 8 articles were at low risk of bias. The meta-analysis results showed that patients in the delirium group had a higher probability of postoperative hypoxemia [odds ratio (OR) =1.65, 95% confidence interval (CI): 1.28-2.13, P<0.01], longer postoperative duration of ventilator assistance (OR =3.05, 95% CI: 2.47-3.77, P<0.01), higher incidence of renal insufficiency (OR =1.86, 95% CI: 1.33-2.58, P<0.01), lower hemoglobin levels (OR =0.33, 95% CI: 0.23-0.48, P<0.01), longer postoperative stay duration in the intensive care unit (ICU) (OR =2.25, 95% CI: 2.13-2.37, P<0.01), longer duration of hospitalization (OR =2.74, 95% CI: 2.37-3.16, P<0.01), and higher postoperative Acute Physiology and Chronic Health Evaluation II (APACHE II) scores (OR =1.01, 95% CI: 0.90-1.12, P=0.92). Conclusions: Post-op aortic dissection in patients with acute type A diabetes should be monitored for oxygen and blood levels. When patients had prolonged mechanical ventilation, renal insufficiency, decreased hemoglobin, and prolonged ICU stay, timely intervention is needed to prevent the high-risk factors of postoperative delirium.

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Postoperative atrial fibrillation (POAF) is a common complication of coronary artery bypass grafting (CABG) procedures. However, the molecular mechanism of POAF remains poorly understood, hence the absence of effective prevention strategies. Here we used targeted metabolomics on pericardial fluid and serum samples from CABG patients to investigate POAF-associated metabolic alterations and related risk prediction of new-onset AF. Nine differential metabolites in various metabolic pathways were found in both pericardial fluid and serum samples from patients with POAF and without POAF. By using machine learning algorithms and regression models, a 4-metabolite (aceglutamide, ornithine, methionine, and arginine) risk prediction model was constructed and showed accurate performance in predicting POAF in both discovery and validation sets. This work extends the metabolic insights of the cardiac microenvironment and blood in patients with POAF and paves the way for the use of targeted metabolomics for predicting POAF in patients with CABG surgery.

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Aramid nanofibers (ANFs) have great potential for civil and military applications due to their remarkable mechanical modulus, excellent chemical reliability, and superior thermostability. Unfortunately, the weak combination of neighboring ANFs limits the mechanical properties of ANF-based materials owing to their inherent rigidity and chemical inertness. Herein, high-performance nanopapers are fabricated by introducing a tiny amount of cellulose nanofibrils (CNFs) to serve as reinforcing blocks via vacuum filtration. As a result of the formation of nanosized building blocks and hydrogen-bonding interaction of CNFs, the resultant ANF/CNF nanopaper yields a record-high tensile strength (406.43 ± 16.93 MPa) and toughness (86.13 ± 5.22 MJ m-3), which are 1.8 and 4.3 times higher than those of the pure ANF nanopaper, respectively. When normalized by weight, the specific tensile strength of the nanopaper is as high as 307.90 MPa·g-1·cm3, which is even significantly superior to that of titanium alloys (257 MPa·g-1·cm3). The ANF/CNF nanopaper also possesses excellent dielectric strength (53.42 kV mm-1), superior UV-shielding performance (≥99.999% absorption for ultraviolet radiation), and a favorable thermostability (Tonset = 530 °C). This study proposes a new design strategy for developing ultrathin ANF-based nanopapers combined with high reliability and thermostability for application in high-end electrical insulation fields, such as 5G communication, wearable electronics, and artificial intelligence.

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BACKGROUND: Bilateral internal mammary artery (BIMA) grafting has a good long-term survival rate and graft patency rate, but it is only recommended in young patients due to its high technical requirements and high incidence of sternal complications. Previous studies indicated that BIMA grafting has a significant benefit in patients aged 50-59 years, but this benefit does not extend to patients aged > 60 years. Thus, this study was designed to analyse the immediate artery graft function, short-term (3 months) results, and experience in preventing sternal complications for BIMA grafting in elderly patients (60-75 years old). METHODS: Clinical records and echocardiographic and coronary artery computed tomography angiography data of 155 patients who underwent BIMA grafting for coronary artery disease between 2015 and 2017 in our hospital were analysed retrospectively to summarise the operative experience and short-term (3 months) results. Patients were divided into two groups: Group A (n = 95), aged < 60 years and Group B (n = 60), aged 60-75 years. The operation time, aortic clamp time, and cardiopulmonary bypass time of these two groups were compared to analyse the operation difficulty and the flow and pulsatility index were compared to analyse the immediate artery graft function. The left ventricular end-diastolic dimension (LVEDD) and left ventricular ejection fraction (LVEF) of these two groups were compared to analyse heart function. RESULTS: There were no significant differences in the operation time, aortic clamp time, and cardiopulmonary bypass time as well as the flow and pulsatility index between these two groups (P > 0.05). There was no significant difference in the incidence of sternal wound complications, graft occlusion, and other common complications 3 months post-BIMA grafting between these two groups (P > 0.05). Furthermore, there was no significant difference in LVEDD and LVEF between the groups 3 months post-operation (P > 0.05). CONCLUSIONS: BIMA grafting was safe and effective for older patients (60-75 years). Similar to younger patients (< 60 years), BIMA grafting in elderly patients (60-75 years) can also achieve a satisfactory short-term (3 months) result. Thus, advanced age (60-75 years) should not be a contraindication for BIMA grafting.

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BACKGROUND: Mitral valve replacement with the total leaflet preservation technique can yield good results; however, its development is limited by patient-valve mismatch. Therefore, we compared the efficacies of the modified total leaflet preservation technique, posterior leaflet preservation technique, and no leaflet preservation technique in mitral valve replacement. METHODS: Clinical records and echocardiographic data of 180 patients who underwent mitral valve replacement for rheumatic mitral valve disease between 2009 and 2017 were analysed retrospectively to summarise the operative experience and short-term (six months) results. The patients were divided into three groups: group A (n = 62), treated with the modified total leaflet preservation technique; group B (n = 80), treated with the posterior leaflet preservation technique; and group C (n = 38), treated with the no leaflet preservation technique. RESULTS: No significant difference in the preoperative clinical data was noted between the groups (p > 0.05). The clamp and recovery times of group A were longer (p < 0.05) and shorter (p < 0.05), respectively, than those of groups B and C. The postoperative left ventricular end-diastolic diameter, left ventricular end-systolic diameter, and left ventricular ejection fraction of group A were significantly better than those of groups B and C. The incidence of low cardiac output syndrome in group A was lower than that in group C (p < 0.05). There was no postoperative left ventricular posterior wall rupture or mechanical valve dysfunction in group A. CONCLUSIONS: The short-term results of the modified total leaflet preservation technique were better than those of the other techniques. This technique is also suitable for patients with rheumatic mitral valve stenosis.

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