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Vertically stacked van der Waals (vdW) heterostructures exhibit unique electronic, optical, and thermal properties that can be manipulated by twist-angle engineering. However, the weak phononic coupling at a bilayer interface imposes a fundamental thermal bottleneck for future two-dimensional devices. Using ultrafast electron diffraction, we directly investigated photoinduced nonequilibrium phonon dynamics in MoS2/WS2 at 4° twist angle and WSe2/MoSe2 heterobilayers with twist angles of 7°, 16°, and 25°. We identified an interlayer heat transfer channel with a characteristic timescale of ~20 picoseconds, about one order of magnitude faster than molecular dynamics simulations assuming initial intralayer thermalization. Atomistic calculations involving phonon-phonon scattering suggest that this process originates from the nonthermal phonon population following the initial interlayer charge transfer and scattering. Our findings present an avenue for thermal management in vdW heterostructures by tailoring nonequilibrium phonon populations.

Background: In this systematic review and meta‐analysis, we aimed to validate the predictive role of atrial fibrillation (AF) termination in long‐term arrhythmia recurrence. Method: Our search encompassed databases including MEDLINE, EMBASE, PubMed, and the Cochrane Library up to August 1, 2021. Three independent reviewers conducted screening and data extraction. The data included ablation strategy, recurrence mode, AF termination mode, numbers of patients, and recurrence cases in the termination and nontermination groups. The primary endpoint was the recurrence of atrial arrhythmia at long‐term follow‐up (≥ 12 months). Results: Our analysis included 22 publications, with 11 prospective studies being eligible for further meta‐analysis. Among these, 14 studies reported significantly lower rates of arrhythmia recurrence in the AF termination group compared to the nontermination group. Among seven studies involving 1114 patients that examined single procedure outcomes, the pooled estimated effect was RR 0.78 (95% CI 0.68–1.90) with an I2 value of 57%. Subgroup analysis focusing on termination mode as sinus rhythm yielded a pooled estimated effect of RR 0.74 (95% CI 0.59–0.92) with an I2 value of 47%. Additionally, analysis of seven studies involving 1433 patients for repeat procedures demonstrated a significant preference for the AF termination group (RR 0.83, 95% CI 0.71–0.97, I2 = 84%). Subgroup analysis indicated reduced heterogeneity when the termination mode was sinus rhythm (RR 0.68, 95% CI 0.51–0.90, I2 = 57%). Conclusion: Our study establishes that AF termination serves as an effective predictor for the success of persistent AF ablation procedures. This finding holds potential implications for clinical practice and contributes to our understanding of long‐term arrhythmia recurrence in the context of AF termination. [ABSTRACT FROM AUTHOR]

Background: There is limited available data regarding the impact of cycle length (CL) prolongation when converting atrial fibrillation (AF) to organized atrial tachycardia (AT) and its effect on clinical outcomes. Methods and Method: We retrospectively screened and included a cohort of 132 patients with persistent or long‐standing persistent AF who underwent circumferential pulmonary vein isolation (CPVI) and left atrial substrate modification (LASM) between January 2015 and October 2019. In all 132 consecutive patients, persistent AF was successfully converted into organized AT. For cases with recurrence after a 3‐month blanking period, a repeat procedure was conducted. Results: We observed a notable prolongation in CL after ablation (average increase of 56.6 ± 30 ms). Following a median follow‐up duration of 9.5 ± 5.1 months, 27 patients experienced recurrence. Through receiver operating curve (ROC) analysis, a prolonged CL cut‐off of 42.5 ms was identified, with a specificity of 71% and a sensitivity of 59.4%. Patients were categorized into two groups: those with CL less than 42.5 ms (group A, n = 48) and those with CL more than 42.5 ms (group B, n = 84). The Kaplan–Meier survival curves demonstrated a significantly higher recurrence‐free rate after catheter ablation in group B compared to group A (p = 0.002). Conclusions: Upon termination of persistent AF into AT during ablation, it was found that CL prolongation beyond 42.5 ms was associated with improved freedom from arrhythmia. [ABSTRACT FROM AUTHOR]

We present an experimental demonstration of ultrafast electron diffraction (UED) with THz-driven electron bunch compression and time-stamping that enables UED probes with improved temporal resolution. Through THz-driven longitudinal bunch compression, a compression factor of approximately four is achieved. Moreover, the time-of-arrival jitter between the compressed electron bunch and a pump laser pulse is suppressed by a factor of three. Simultaneously, the THz interaction imparts a transverse spatiotemporal correlation on the electron distribution, which we utilize to further enhance the precision of time-resolved UED measurements. We use this technique to probe single-crystal gold nanofilms and reveal transient oscillations in the THz near fields with a temporal resolution down to 50 fs. These oscillations were previously beyond reach in the absence of THz compression and time-stamping. [ABSTRACT FROM AUTHOR]

Pulsed field ablation (PFA), a nonthermal ablative mechanism, has been proven to be effective and safe in clinical application. To date, PFA has been used for only atrial fibrillation (AF) ablation in limited clinical trials. The present study describes a case of paroxysmal AF in which mitral and cavotricuspid isthmus (CTI)-dependent atrial flutter was discovered incidentally during PFA operation and successfully ablated with PFA. This is the first medical record of PFA for AF combined with mitral and CTI atrial flutter. The present case report revealed that PFA can be independently used to treat complex arrhythmias, similar to radiofrequency (RF) ablation, without the need for assistance from other ablation methods. Concurrently, the present study, to the best of the authors' knowledge is the first to report a case using a point-to-point PFA ablation strategy for isthmus ablation. This highlights the potential of PFA in treating diverse arrhythmias across different regions, such as the mitral isthmus and other intricate areas, utilizing a point-to-point PFA ablation strategy., Competing Interests: The authors declare that they have no competing interests., (Copyright: © 2024 He et al.)

By designing a liquid crystal cell with comb electrode structure, the alignment modulation of nematic liquid crystal in the cell can be realized after the electric field is applied. In different orientation regions, the incident laser beam can deflect at different angles. At the same time, by changing the incident angle of the laser beam, the reflection modulation of the laser beam on the interface of the liquid crystal molecular orientation change can be realized. Based on the above discussion, we then demonstrate the modulation of liquid crystal molecular orientation arrays on nematicon pairs. In different orientation regions of liquid crystal molecules, nematicon pairs can exhibit various combinations of deflections, and these deflection angles are modulable under external fields. Deflection and modulation of nematicon pairs have potential applications in optical routing and optical communication.

Aim: We present the long-term outcomes as well as their correlation with tumor size in 127 consecutive patients harboring large MSWM after microsurgical treatment., Material and Methods: The retrospective analysis of clinical data and follow-up data of 127 microsurgical treated patients with MSWM was performed. The mean maximum diameter of tumors was 5.2cm (ranged 1.5-10.0cm)., Results: 104 cases (81.9%) achieved gross total resection. There was no operative mortality. Detailed follow-up data was available in 120 cases for a mean duration of 81.6 months (12-216 months). The permanent morbidity was 14.2%. The mean KPS score 1 year after surgery was 90.6 (ranged 60-100). Among 74 patients of preoperative visual acuity (VA) impairment, postoperative VA improved in 42 cases (56.8%), unchanged in 30 (40.5%), and deteriorated in 2 (2.7%). MR images revealed tumor recurrence after total resection in 10 cases (10.2%) and tumor progression after subtotal resection in 10 cases (45.5%)., Conclusion: Tumor recurrence was the major risk in the long run, thus the initial surgery was extremely important and hence should be aggressive. The size of tumor affected the extent of tumor removal determining clinical outcomes including VA improvement and KPS score immediately after surgery; however, it was not correlated with long-term overall outcomes.

Aim: To explore the expansion and differentiation of hepatocytoid cell induced from myeloid mesenchymal stem cell (MSC) in vitro, in order to find suitable resource of hepatocytes for bioartificial liver or liver transplantation., Methods: The rat myeloid MSC was isolated and divided into three groups which were cultured by Friedensteion method, and then were induced by culture fluid, culture fluid plus cholestatic serum and culture fluid plus hepatocyte growth factor (HGF), respectively. Hepatocytoid cell as well as expression of CK18 and AFP was observed by immunohistochemistry., Results: After the induction for 21 d, hepatocytoid cell was observed, and its expression of CK18 and AFP was detected by immunohistochemistry in MSC cultured with cholestatic serum. Furthermore, on the 35th d, albumin mRNA was expressed in the cell, suggesting the inducing effect was similar to that by HGF., Conclusion: Rat myeloid MSC can differentiate into hepatocyte lineage under appropriate condition. This method is easy to operate.

Background: The mortality rate of heavy type hepatitis is high. No special treatment is available except general treatment. This multicenter clinical study was designed to observe the safety and efficacy of promoting hepatic growth factor (PHGF) in the treatment of heavy type hepatitis and severe chronic hepatitis., Methods: 347 patients with heavy type hepatitis and 324 with severe chronic hepatitis were subjected to administration of 120 microg of PHGF per day for 4 weeks on the basis of general treatment. Those who were being effectively treated would last additional 2 to 4 weeks. Blood routine, urine routine, blood urea nitrogen (BUN), blood creatinine (Cr), blood ammonia, alpha fetoprotein (AFP), electrolyte, alanine transaminase (ALT), aspartate transaminase (AST), serum total bilirubin (TBIL), serum direct bilirubin (DBIL), prothrombin time activity (PTA), total protein (TP) and albumin (ALB) were detected in the patients before treatment, 2 weeks after treatment, and at the end of the treatment. Any side-effect would be recorded., Results: In the patients with severe chronic hepatitis, the total effective rate of the treatment was 88.9%. The levels of ALT, AST and TBIL decreased significantly (P<0.001), whereas those of PTA and ALB increased significantly (P<0.001), and the level of AFP increased slightly. In patients with heavy type hepatitis, the total effective rate of this treatment was 78.4%, and patients at different stage showed different results. The total effective rates of patients with early, medium and terminal stage heavy type hepatitis were 89.9%, 84.8% and 27.5%, respectively. No severe side-effect was shown., Conclusion: PHGF is effective and safe in the treatment of patients with heavy type hepatitis and severe chronic hepatitis. But it should be administered early in patients with heavy type hepatitis so as to get better curative effects.

Aim: To study the effects of pentoxifylline (PTX) on the content of hepatic TGF-beta1, type I and type III collagen in schistosomiasis japonica mice with liver fibrosis and its mechanism of anti-fibrosis., Methods: Forty mice with schistosomiasis were divided into four groups: one group as control without any treatment, other three were treated with Praziquantel 500 mg/(kg x d)for 2 d, high dose PTX 360 mg/(kg x d) for 8 wk, and low dose PTX 180 mg/(kg x d) for 8 wk respectively. Immunohistochemical technique and multimedia color pathographic analysis system were applied to observe the content change of hepatic TGF-beta1, type I and type III collagen in schistosomiasis japonica mice with liver fibrosis before and after PTX treatment., Results: Effects of PTX on the content change of hepatic TGF-beta1, type I and type III collagen in schistosomiasis japonica mice with liver fibrosis were related to the dosage of PTX, high dose PTX treated group could significantly reduce the content of TGF-beta1 (0.709+/-0.111), type I (0.644+/-0.108) and type III (0.654+/-0.152) collagen compared with those of control group (0.883+/-0.140, 0.771+/-0.156, 0.822+/-0.129) with statistical significance (P<0.05). Low dose PTX could also reduce the hepatic content of TGF-beta1 (0.752+/-0.152), type I (0.733+/-0.117) and type III (0.788+/-0.147) collagen, but without statistical significance (P>0.05). Both high dose and low dose PTX groups have significant differences on the content of TGF-beta1, type I and type III collagen (P<0.05, P<0.05, P<0.01, respectively)., Conclusion: High dose of PTX treatment could reduce the content of hepatic TGF-beta1, type I and type III collagen significantly in schistosomiasis japonica mice with liver fibrosis, and thus plays its role of antifibrosis.

AIM:To explore the relationship between endoinfection caused by intestinal flora translocation and multiple organ dysfunction in hepatic failure.METHODS:By using the quantitative bacteria culture, bacteria colony was counted in GI tract, bile duct and mesenteric lymphonodus in rat hepatic failure model.RESULTS:Intestinal flora migrated up to the upper GI tract and overgrew in stomach and jejunum in rats with hepatic failure.The number of bacteria colonies in the specimens of stomach, jejunum and ileum were 4.7X10(4)/mL, 2.1X10(5)/mL, 5.5X10(6)/mL in experiment group and 4.6X10(2)/mL, 6.1X10(1)/mL, 2.4X10(3)/mL in control group respectively (P < 0.05 ). Bacteria in bile duct and mesenteric lymphonodus of hepatic failure rats were also cultured. Extensive damages of gastrointestinal mucosa caused by bacterial overgrowth were observed.CONCLUSION:Intestinal flora translocation and overgrowth in stomach and jejunum formed an endoinfectious source and caused obvious pathological injury of gastrointestinal mucosa, which play a very important role in developing abdominal distension, toxic intestinal expansion, alimentary tract haemorrhage and endotoxemia in patients with hepatic failure.