Electric Field Effect in Multilayer Cr2Ge2Te6: a Ferromagnetic Two-Dimensional Material

The emergence of two-dimensional (2D) materials has attracted a great deal of attention due to their fascinating physical properties and potential applications for future nanoelectronic devices. Since the first isolation of graphene, a Dirac material, a large family of new functional 2D materials have been discovered and characterized, including insulating 2D boron nitride, semiconducting 2D transition metal dichalcogenides and black phosphorus, and superconducting 2D bismuth strontium calcium copper oxide, molybdenum disulphide and niobium selenide, etc. Here, we report the identification of ferromagnetic thin flakes of Cr2Ge2Te6 (CGT) with thickness down to a few nanometers, which provides a very important piece to the van der Waals structures consisting of various 2D materials. We further demonstrate the giant modulation of the channel resistance of 2D CGT devices via electric field effect. Our results illustrate the gate voltage tunability of 2D CGT and the potential of CGT, a ferromagnetic 2D material, as a new functional quantum material for applications in future nanoelectronics and spintronics.Comment: To appear in 2D Material

MicroRNA-483 amelioration of experimental pulmonary hypertension.

Endothelial dysfunction is critically involved in the pathogenesis of pulmonary arterial hypertension (PAH) and that exogenously administered microRNA may be of therapeutic benefit. Lower levels of miR-483 were found in serum from patients with idiopathic pulmonary arterial hypertension (IPAH), particularly those with more severe disease. RNA-seq and bioinformatics analyses showed that miR-483 targets several PAH-related genes, including transforming growth factor-β (TGF-β), TGF-β receptor 2 (TGFBR2), β-catenin, connective tissue growth factor (CTGF), interleukin-1β (IL-1β), and endothelin-1 (ET-1). Overexpression of miR-483 in ECs inhibited inflammatory and fibrogenic responses, revealed by the decreased expression of TGF-β, TGFBR2, β-catenin, CTGF, IL-1β, and ET-1. In contrast, inhibition of miR-483 increased these genes in ECs. Rats with EC-specific miR-483 overexpression exhibited ameliorated pulmonary hypertension (PH) and reduced right ventricular hypertrophy on challenge with monocrotaline (MCT) or Sugen + hypoxia. A reversal effect was observed in rats that received MCT with inhaled lentivirus overexpressing miR-483. These results indicate that PAH is associated with a reduced level of miR-483 and that miR-483 might reduce experimental PH by inhibition of multiple adverse responses

A Dirac-type theorem for arbitrary Hamiltonian HH-linked digraphs

Given any digraph $D$, let $\mathcal{P}(D)$ be the family of all directed paths in $D$, and let $H$ be a digraph with the arc set $A(H)=\{a_1, \ldots, a_k\}$. The digraph $D$ is called arbitrary Hamiltonian $H$-linked if for any injective mapping $f: V(H)\rightarrow V(D)$ and any integer set $\mathcal{N}=\{n_1, \ldots, n_k\}$ with $n_i\geq4$ for each $i\in\{1, \ldots, k\}$, there exists a mapping $g: A(H)\rightarrow \mathcal{P}(D)$ such that for every arc $a_i=uv$, $g(a_i)$ is a directed path from $f(u)$ to $f(v)$ of length $n_i$, and different arcs are mapped into internally vertex-disjoint directed paths in $D$, and $\bigcup_{i\in[k]}V(g(a_i))=V(D)$. In this paper, we prove that for any digraph $H$ with $k$ arcs and $\delta(H)\geq1$, every digraph of sufficiently large order $n$ with minimum in- and out-degree at least $n/2+k$ is arbitrary Hamiltonian $H$-linked. Furthermore, we show that the lower bound is best possible. Our main result extends some work of K\"{u}hn and Osthus et al. \cite{20081,20082} and Ferrara, Jacobson and Pfender \cite{Jacobson}. Besides, as a corollary of our main theorem, we solve a conjecture of Wang \cite{Wang} for sufficiently large graphs

Can Shaker Potassium Channels be Locked in the Deactivated State?

For structural studies it would be useful to constrain the voltage sensor of a voltage-gated channel in its deactivated state. Here we consider one Shaker potassium channel mutant and speculate about others that might allow the channel to remain deactivated at zero membrane potential. Ionic and gating currents of F370C Shaker, expressed in Xenopus oocytes, were recorded in patches with internal application of the methanethiosulfonate reagent MTSET. It appears that the voltage dependence of voltage sensor movement is strongly shifted by reaction with internal MTSET, such that the voltage sensors appear to remain deactivated even at positive potentials. A disadvantage of this construct is that the rate of modification of voltage sensors by MTSET is quite low, ∼0.17 mM−1·s−1 at −80 mV, and is expected to be much lower at depolarized potentials

Nanotechnology applications in geothermal energy systems: Advances, challenges and opportunities

Geothermal energy offers a sustainable solution to meet growing energy needs while mitigating environmental concerns associated with conventional fossil fuel sources. Meanwhile, nanotechnology presents innovative solutions to enhance the performance of renewable energy systems. However, its specific applications in geothermal energy are a dynamic field and have not been systematically reviewed. This paper presents an overview of the latest advancements in utilizing nanotechnology to enhance geothermal energy systems. The essential role of nanotechnology is examined across the entire life-cycle of geothermal development and utilization, encompassing various aspects including geothermal well construction, geothermal reservoir characterization, scaling and corrosion prevention, and resource recovery. The results suggest that nanotechnology holds significant promise for improving the efficiency, longevity, and profitability of geothermal energy systems. Further more, this paper outlines the potential challenges associated with nanotechnology adoption in technical, environmental, and economic terms, and offers strategies for mitigating them. Finally, the paper discusses some future perspectives on how nanotechnology can further advance geothermal energy, contributing to the global transition to a clean and renewable energy future.Document Type: Current minireviewCited as: Meng, B., Yan, G., He, P., Zhou, Q., Xu, W., Qian, Y. Nanotechnology applications in geothermal energy systems: Advances, challenges and opportunities. Advances in Geo-Energy Research, 2025, 15(2): 172-180. https://doi.org/10.46690/ager.2025.02.0