Intrinsic edge states and strain-tunable spin textures in the Janus 1T-VTeCl monolayer.

Using first-principles calculations and micro-magnetic simulations, we investigate the electronic structures, the effect of biaxial strain on the topological characteristics, magnetic anisotropy energy (MAE), Dzyaloshinskii-Moriya interaction (DMI) and spin textures in the Janus 1T phase VTeCl (1T-VTeCl) monolayer. Our results show that 1T-VTeCl has an intrinsic edge state, and a topological phase transition with a sizeable band gap is achieved by applying biaxial strain. Interestingly, the MAE can be switched from the in-plane to the off-plane with a compressive strain of -5%. Microscopically, the origin of MAE is mainly associated with the large spin-orbit coupling (SOC) from the heavy nonmagnetic Te atoms rather than that from the V atoms. Furthermore, the induced DMI (0.09 meV) can occur stabilizing magnetic merons without applying temperatures and magnetic fields. Then, the skyrmions, frustrated antiferromagnetism and vortex are induced after applying a suitable compressive strain. Our study provides compelling evidence that the 1T-VTeCl monolayer with topological properties holds great potential for application in spintronic devices, as well as information storage devices based on different magnetic phases achievable through strain engineering.

Electronic properties, skyrmions and bimerons in Janus CrXY (X, Y = S, Se, Te, Cl, Br, I, and X ≠ Y) monolayers.

Using first-principles calculations, we systematically investigate the electronic properties, chiral skyrmions and bimerons in two-dimensional (2D) Janus CrXY (X, Y = S, Se, Te, Cl, Br, I, and X ≠ Y) monolayers. We found that the categories of nonmagnetic atoms (X and Y in CrXY) determine whether CrXY is a ferromagnetic metal or a semiconductor. Unexpectedly, the CrBrS monolayer of these CrXY materials is a room temperature ferromagnetic semiconductor with a Curie temperature of 303 K, and it possesses an off-plane magnetic anisotropy energy of 0.06 meV. Besides, a strong Dzyaloshinskii-Moriya interaction (DMI) of 3.10 meV is found in CrTeI and is mainly induced by the strong spin-orbit coupling of the nonmagnetic atoms Te(I) rather than that of the magnetic Cr atoms. Furthermore, using micromagnetic simulations, skyrmions can be stabilized in CrSeBr without external magnetic fields. More importantly, the bimerons in CrSeCl with in-plane magnetic anisotropy can be transformed into skyrmions or a ferromagnetic state by controlling the direction of external magnetic fields. Our work investigates fourteen kinds of Janus monolayers, serving as guidelines for materials research on DMI, skyrmions and bimerons.

Exosome-transmitted circCABIN1 promotes temozolomide resistance in glioblastoma via sustaining ErbB downstream signaling.

Although temozolomide (TMZ) provides significant clinical benefit for glioblastoma (GBM), responses are limited by the emergence of acquired resistance. Here, we demonstrate that exosomal circCABIN1 secreted from TMZ-resistant cells was packaged into exosomes and then disseminated TMZ resistance of receipt cells. CircCABIN1 could be cyclized by eukaryotic translation initiation factor 4A3 (EIF4A3) and is highly expressed in GBM tissues and glioma stem cells (GSCs). CircCABIN1 is required for the self-renewal maintenance of GSCs to initiate acquired resistance. Mechanistically, circCABIN1 regulated the expression of olfactomedin-like 3 (OLFML3) by sponging miR-637. Moreover, upregulation of OLFML3 activating the ErbB signaling pathway and ultimately contributing to stemness reprogramming and TMZ resistance. Treatment of GBM orthotopic mice xenografts with engineered exosomes targeting circCABIN1 and OLFML3 provided prominent targetability and had significantly improved antitumor activity of TMZ. In summary, our work proposed a novel mechanism for drug resistance transmission in GBM and provided evidence that engineered exosomes are a promising clinical tool for cancer prevention and therapy.

Stepwise Stiffening Chromophore Strategy Realizes a Series of Ultralong Blue Room-Temperature Phosphorescent Materials.

Ultralong room-temperature phosphorescent (URTP) materials have attracted wide attention in anti-counterfeiting, optoelectronic display, and bio-imaging due to their special optical properties. However, room-temperature blue phosphorescent materials are very scarce during applications because of the need to simultaneously populate and stabilize high-energy excited states. In this work, a stepwise stiffening chromophore strategy is proposed to suppress non-radiative jump by continuously reducing the internal spin of the chromophore, and successfully developing a series of blue phosphorescent materials. Phosphorescence lifetimes of more than 3 s are achieved, with the longest lifetime reaching 5.44 s and lasting more than 70 s in the naked eye. As far as is know, this is the best result that has been reported. By adjusting the chromophore conjugation, multicolor phosphorescences from cyan to green have been realized. In addition, these chromophores exhibit the same excellent optical properties in urea and polyvinyl alcohmance (PVA). Finally, these materials are successfully applied to luminescent displays.

Strain-induced magnetic phase transition, magnetic anisotropy switching and bilayer antiferromagnetic skyrmions in van der Waals magnet CrTe2.

In recent years, considerable attention has been paid to the research of peculiar magnetism in two-dimensional (2D) van der Waals (vdW) layered materials. Here, we unveil the major features and deep physical mechanisms of a magnetic phase transition and magnetic anisotropy switching in monolayer CrTe2 and antiferromagnetic (AFM) skyrmions in bilayer CrTe2via first-principles calculations and micromagnetic simulations. We find that a magnetic phase transition from stripy-type AFM to ferromagnetic (FM) order can be induced by applying a tensile strain of 3%. More interestingly, the magnetic easy axis can be switched between in-plane and off-plane via adjusting the magnitude of strain. Besides, the topologically protected bilayer AFM skyrmion is stabilized by a large Dzyaloshinskii-Moriya interaction (DMI) of 1.43 meV and a skyrmion lattice can be induced by a magnetic field of 6.9 T at 100 K. Different from the monolayer magnetic skyrmion, the bilayer AFM skyrmion is more promising in spintronic nanodevices owing to the suppressed skyrmion Hall effect. Our findings clarify the underlying mechanisms of the strain-tunable magnetic phase transition, magnetic anisotropy switching and bilayer AFM skyrmions in vdW magnet CrTe2, and also highlight the promising applications of CrTe2 in next-generation information storage devices.

Prophylactic inguinal lymphadenectomy for high-risk cN0 penile cancer: The optimal surgical timing.

Background: Few reports have investigated the oncologically safe timing of prophylactic inguinal lymphadenectomy for penile cancer patients with clinically normal inguinal lymph nodes (cN0), particularly those who received delayed surgical treatment. Methods: The study included pT1aG2, pT1b-3G1-3 cN0M0 patients with penile cancer who received prophylactic bilateral inguinal lymph nodes dissection (ILND) at the Department of Urology of Tangdu Hospital between October 2002 and August 2019. Patients who received simultaneous resection of primary tumor and inguinal lymph nodes were assigned to the immediate group, while the rest were assigned to the delayed group. The optimal timing of lymphadenectomy was determined based on the time-dependent ROC curves. The disease-specific survival (DSS) was estimated based on the Kaplan-Meier curve. Cox regression analysis was used to evaluate the associations between DSS and the timing of lymphadenectomy and tumor characteristics. The analyses were repeated after stabilized inverse probability of treatment weighting adjustment. Results: A total of 87 patients were enrolled in the study, 35 of them in the immediate group and 52 in the delayed group. The median (range) interval time between primary tumor resection and ILND of the delayed group was 85 (29-225) days. Multivariable Cox analysis demonstrated that immediate lymphadenectomy was associated with a significant survival benefit (HR, 0.11; 95% CI, 0.02-0.57; p = 0.009). An index of 3.5 months was determined as the optimal cut-point for dichotomization in the delayed group. In high-risk patients who received delayed surgical treatment, prophylactic inguinal lymphadenectomy within 3.5 months was associated with a significantly better DSS compared to dissection after 3.5months (77.8% and 0%, respectively; log-rank p<0.001). Conclusions: Immediate and prophylactic inguinal lymphadenectomy in high-risk cN0 patients (pT1bG3 and all higher stage tumours) with penile cancer improves survival. For those patients at high risk who received delayed surgical treatment for any reason, within 3.5 months after resection of the primary tumor seems to be an oncologically safe window for prophylactic inguinal lymphadenectomy.

Detailed identification of epidermal growth factor receptor mutations in lung adenocarcinoma: Combining radiomics with machine learning.

PURPOSE: To investigate the use of radiomics in the in-depth identification of epidermal growth factor receptor (EGFR) mutation status in patients with lung adenocarcinoma. METHODS: Computed tomography images of 438 patients with lung adenocarcinoma were collected in two different institutions, and 496 radiomic features were extracted. In the training set, lasso logistic regression was used to establish radiomic signatures. Combining radiomic index and clinical features, five machine learning methods, and a tenfold cross-validation strategy were used to establish combined models for EGFR+ vs EGFR- , and 19Del vs L858R, groups. The predictive power of the models was then evaluated using an independent external validation cohort. RESULTS: In the EGFR+ vs EGFR- and 19Del vs L858R groups, radiomic signatures consisting of 12 and 7 radiomic features were established, respectively; the area under the curves (AUCs) of the lasso logistic regression model on the validation set was 0.76 and 0.71, respectively. After inclusion of the clinical features, the maximum AUC of combined models on the validation set was 0.79 and 0.74, respectively. Logistic regression analysis showed good performance in the two groups, with AUCs of 0.79 and 0.71 on the validation set. Additionally, the AUC of combined models in the EGFR+ vs EGFR- group was higher than that of the 19Del vs L858R group. CONCLUSIONS: Our study shows the potential of radiomics to predict EGFR mutation status. There are imaging phenotypic differences between EGFR+ and EGFR- , and between 19Del and L858R; these can be used to allow patients with lung adenocarcinoma to choose more appropriate and personalized treatment options.