Valley depolarization in monolayer WSe2

We have systematically examined the circular polarization of monolayer WSe2 at different temperature, excitation energy and exciton density. The valley depolarization in WSe2 is experimentally confirmed to be governed by the intervalley electron-hole exchange interaction. More importantly, a non-monotonic dependence of valley circular polarization on the excitation power density has been observed, providing the experimental evidence for the non-monotonic dependence of exciton intervalley scattering rate on the excited exciton density. The physical origination of our experimental observations has been proposed, which is in analogy to the D'yakonov-Perel' mechanism that is operative in conventional GaAs quantum well systems. Our experimental results are fundamentally important for well understanding the valley psudospin relaxation in atomically thin transition metal dichalcogenides

Clinicopathological Features and Prognostic Factors of Colorectal Neuroendocrine Neoplasms

Background. Limited research is available regarding colorectal NENs and the prognostic factors remain controversial. Materials and Methods. A total of 68 patients with colorectal NENs were studied retrospectively. Clinical characteristics and prognosis between colonic and rectal NENs were compared. The Cox regression models were used to evaluate the predictive capacity. Results. Of the 68 colorectal NENs patients, 43 (63.2%) had rectal NENs, and 25 (36.8%) had colonic NENs. Compared with rectal NENs, colonic NENs more frequently exhibited larger tumor size (P<0.0001) and distant metastasis (P<0.0001). Colonic NENs had a worse prognosis (P=0.027), with 5-year overall survival rates of 66.7% versus 88.1%. NET, NEC, and MANEC were noted in 61.8%, 23.5%, and 14.7% of patients, respectively. Multivariate analyses revealed that tumor location was not an independent prognostic factor (P=0.081), but tumor size (P=0.037) and pathological classification (P=0.012) were independent prognostic factors. Conclusion. Significant differences exist between colonic and rectal NENs. Multivariate analysis indicated that tumor size and pathological classification were associated with prognosis. Tumor location was not an independent factor. The worse outcome of colonic NENs observed in clinical practice might be due not only to the biological differences, but also to larger tumor size in colonic NENs caused by the delayed diagnosis

Vibration Suppression of a Coupled Aircraft Wing with Finite-Time Convergence

A nonlinear coupled wing model subject to unknown external disturbances is proposed in this paper. Since the model is modeled by partial differential equations, the traditional control design scheme based on the ordinary differential equation model is not applicable, and the control law design becomes very complex. In this paper, a new antidisturbance boundary control scheme based on a finite time convergent disturbance observer is proposed. The control laws are designed based on the new disturbance observers to make the external disturbance errors converge to zero in a finite time and ensure the uniformly bounded stability of the controlled system. Finally, the effectiveness of the controllers and the finite-time convergence of disturbance errors are verified by the simulation and comparison

Sintilimab plus nab-paclitaxel as second-line treatment for advanced biliary tract cancer: study protocol for an investigator-initiated phase 2 trial (NapaSinti trial)

Abstract Background Biliary tract cancer (BTC) is a relatively rare but highly aggressive malignancy. However, there is currently no satisfactory second-line regimen for patients without specific genetic mutations. Nanoparticle albumin–bound paclitaxel, also known as nab-paclitaxel (Abraxane, Bristol Myers Squibb), has shown activity in patients with BTC. Studies investigating the immunogenic features of BTC suggested that checkpoint inhibition may lead to antitumor immune responses. In recent years, improved survival has been observed in patients treated with chemotherapy combined with immunotherapy across multiple cancer types, including BTC. This clinical trial aims to evaluate the efficacy and safety of second-line sintilimab in combination with nab-paclitaxel in advanced BTC patients. Methods The NapaSinti trial is a prospective, nonrandomized, open-label, phase 2 study conducted at a tertiary hospital in Chengdu, China. Eligible patients are those with histologically or cytologically confirmed locally advanced non-resectable or metastatic adenocarcinoma in the biliary tract (including intrahepatic cholangiocarcinoma, extrahepatic cholangiocarcinoma, and gallbladder cancer), aged between 18 and 75 years, with an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, who have experienced disease progression after prior gemcitabine- or fluorouracil-based chemotherapy and have not received taxane or immune checkpoint inhibitor treatment. Enrolled patients will receive intravenous administration of sintilimab 200 mg on day 1 and nab-paclitaxel 125 mg/m2 on days 1 and 8, every three weeks. The primary endpoint is the objective response rate (ORR), while the secondary endpoints include overall survival (OS), progression-free survival (PFS), and safety. Exploratory objectives aim to identify biomarkers and molecular signatures for predicting response or prognosis. Using Simon’s two-stage design, a total of 63 participants will be enrolled in the study. This trial was initiated in March 2022 in China. Discussion The NapaSinti trial evaluates the efficacy and safety of second-line sintilimab plus nab-paclitaxel for advanced biliary tract cancer. Additionally, the trial provides an opportunity for translational research. Trial registration Chinese Clinical Trial Registry ChiCTR2100052118. Registered October 19, 2021