Exciton luminescence and many-body effect of monolayer WS2 at room temperature

Monolayer transition metal dichalcogenides favor the formation of a variety of excitonic quasiparticles,and can serve as an ideal material for exploring room-temperature many-body effects in two-dimensional systems.Here,using mechanically exfoliated monolayer WS;and photoluminescence(PL)spectroscopy,exciton emission peaks are confirmed through temperature-dependent and electric-field-tuned PL spectroscopy.The dependence of exciton concentration on the excitation power density at room temperature is quantitatively analyzed.Exciton concentrations covering four orders of magnitude are divided into three stages.Within the low carrier concentration stage,the system is dominated by excitons,with a small fraction of trions and localized excitons.At the high carrier concentration stage,the localized exciton emission from defects coincides with the emission peak position of trions,resulting in broad spectral characteristics at room temperature.

Distinct Immune Signatures in Peripheral Blood Predict Chemosensitivity in Intrahepatic Cholangiocarcinoma Patients

Intrahepatic cholangiocarcinoma(ICC)is the second most common liver cancer.Chemotherapy remains the main therapeutic strategy for advanced ICC patients,but chemosensitivity varies individually.Here,we applied cytometry by time-of-flight(CyTOF)to establish the immune profile of peripheral blood mononuclear cells(PBMCs)on the single-cell level at indicated time points before,during,and after chemotherapy.Multiplex immunofluorescence staining was applied to examine the spatial distribution of certain immune clusters.Tissue microarrays(TMAs)were used for prognostic evaluation.A total of 20 ICC patients treated with gemcitabine(GEM)were enrolled in our study,including eight cases with good response(R)and 12 cases with non-response(NR).Tremendous changes in PBMC composition,including an increased level of CD4/CD8 double-positive T cells(DPT),were observed after chemotherapy.Patients with higher level of CD4^(+)CD45RO^(+)CXCR3^(+)T cells before treatment had a favorable response to chemotherapy.Our study identified a positive correlation between the percentage of T cell subpopulations and clinical response after chemotherapy,which suggests that it is practical to predict the potential response before treatment by evaluating the proportions of the cell population in PBMCs.

Onjisaponin B derived from Radix Polygalae enhances autophagy and accelerates the degradation of mutant α-Synuclein and Huntingtin in PC-12 cells

OBJECTIVE To investigate the autophagic effect of the compounds from the Chinese medicinal herbs,Radix polygalae as a potential neuroprotective agent that enhances the clearance of mutant Huntingtin andα-synuclein in PC-12 cells.METHODS Radix polygalae was extracted with 75%ethanol using refluxing method,and its quality was assayed by UHPLC-TOF-MS.The autophagic effect of Radix polygalae extract,and its major components including polygalacic acid,senegenin and onjisaponin B were investigated using the green fluorescent protein-light chain 3(GFP-LC3)autophagy detection and Western blot platforms for detecting the autophagic markers,GFP-LC3 puncta formation and LC3Ⅱ expression.The degradation of A53Tα-synuclein and the inhibition of α-synuclein oligo merization related to the Parkinson disease were assayed using Western blot and flow cytometer analysis,respectively.While the cytotoxicity and the degradation of the mutant Huntingtin associated with the Huntingtin disease were investigated using MTT method and flow cytometer analysis.RESULTS Radix polygalae ethanol extract and onjisaponin B improved the GFP-LC3 puncta formation and expression of LC3Ⅱ with time and dose manner,and this induction was activated via AMPK-m TOR and Atg 7 gene pathway.Furthermore,the clearance ofα-synuclein and mutant Huntingtin was enhanced via autophagy induction with the treatment of Radix polygalae ethanol extract and onjisaponin B.CONCLUSION Findings in the current study provide detailed insights into the protective mechanism of a novel autophagy inducer,onjisaponin B,which is valuable for further investigation as a new candidate agent for modulating neurodegenerative disorders through the reduction of toxicity and clearance of mutant proteins in the cellular level.

Stable GeSe thin-film solar cells employing non-toxic SnO_(2)as buffer layer

Germanium monoselenide(GeSe)has attracted significant attention recently for its excellent optoelectronic properties,nontoxicity,and high stability.However,the current best-performance GeSe solar cells usually take toxic CdS as the buffer layer that restricts their practical applications.Here we select non-toxic SnO_(2)as the buffer layer and construct environment-friendly SnO_(2)/GeSe heterojunction solar cells.