We present a simple micromanipulation technique to transfer suspended graphene flakes onto any substrate and to assemble them with small localized gates into mechanical resonators. The mechanical motion of the graphene is detected using an electrical, radio frequency (RF) reflection readout scheme where the time-varying graphene capacitor reflects a RF carrier at f = 5-6 GHz producing modulation sidebands at f ± f(m). A mechanical resonance frequency up to f(m) = 178 MHz is demonstrated. We find both hardening/softening Duffing effects on different samples and obtain a critical amplitude of ~40 pm for the onset of nonlinearity in graphene mechanical resonators. Measurements of the quality factor of the mechanical resonance as a function of dc bias voltage V(dc) indicates that dissipation due to motion-induced displacement currents in graphene electrode is important at high frequencies and large V(dc).
A red shift of the exciton of ZnO nanowires is efficiently produced by bending strain, as demonstrated by a low-temperature (81 K) cathodoluminescence (CL) study of ZnO nanowires bent into L- or S-shapes. The figure shows a nanowire (Fig. a) with the positions of CL measurements marked. The corresponding CL spectra-revealing a peak shift and broadening in the region of the bend-are shown in Figure b.
Cavity optomechanics has served as a platform for studying the interaction between light and micromechanical motion via radiation pressure. Here we observe such phenomena with a graphene mechanical resonator coupled to an electromagnetic mode. We measure thermal motion and backaction cooling in a bilayer graphene resonator coupled to a microwave on-chip cavity. We detect the lowest flexural mode at 24 MHz down to 50 mK, corresponding to roughly mechanical 40 quanta, representing nearly three orders of magnitude lower phonon occupation than recorded to date with graphene resonators.
Background:Glypican-3 (GPC3) has been widely recognized in the progression of liver tumors for several years. The relationship between overexpression of GPC3 and the poorer prognosis of patients with hepatocellular carcinoma (HCC) was performed by 2 meta-analyses. However, there were also some latest literatures that indicated different conclusions distinctly. It is necessary for us to carry out a meta-analysis by adding the latest data from current studies to explore the correlation between GPC3 and prognostic value in HCC.Methods:We conducted a meta-analysis including a total of 14 studies to assess the potential prognostic significance of GPC3 expression for overall survival (OS) and disease-free survival (DFS). The expression of GPC3 was assessed by immunohistochemistry.Results:Fourteen studies with 2364 patients were incorporated in the meta-analysis. The combined hazard ratios (HRs) revealed that the overexpression of GPC3 could forecast a poor OS [n = 2233 in 12 studies, HR = 1.40, 95% confidence interval (95% CI): 1.07–1.85, Z = 2.42, P = .02] and DFS (n = 1308 in 10 studies, HR = 1.61, 95% CI: 1.13–2.30, Z = 2.63, P = .008) in HCC patients. Subgroup treated by hepatectomy indicated that the pooled HR of OS was 1.43 (95% CI: 1.01–2.01, P = .04) and the combined HR of DFS was 1.59 (95% CI: 1.09–2.31, P = .02). The pooled odds ratios (ORs) showed that high GPC3 expression was also extensively associated with worse tumor differentiation, later tumor stage, presence of vascular invasion, and hepatitis B virus (HBV) infection. Subgroup analyses for GPC3 on HCC OS based on the studies categorized by regions, follow-up period, and sample size were also conducted.Conclusion:The meta-analysis indicated that overexpression of GPC3 was significantly associated with poor prognosis in patients with HCC.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.