Valley-Layer Coupling: A New Design Principle for Valleytronics

We introduce the concept of valley-layer coupling (VLC) in two-dimensional materials, where the low-energy electronic states in the emergent valleys have valley-contrasted layer polarization such that each state is spatially localized on the top or bottom super-layer. The VLC enables a direct coupling between valley and gate electric field, opening a new route towards electrically controlled valleytronics. We analyze the symmetry requirements for the system to host VLC, demonstrate our idea via first-principles calculations and model analysis of a concrete 2D material example, and show that an electric, continuous, wide-range, and switchable control of valley polarization can be achieved by VLC. Furthermore, we find that systems with VLC can exhibit other interesting physics, such as valley-contrasting linear dichroism and optical selection of the electric polarization of interlayer excitons.Comment: 6 pages, 4 figure

3,3-Dinitro­azetidinium 2-hy­droxy­benzoate

In the title gem-dinitro­azetidinium 2-hy­droxy­benzoate salt, C3H6N3O4 +·C7H5O3 −, the azetidine ring is virtually planar, with a mean deviation from the plane of 0.0242 Å. The dihedral angle between the two nitro groups is 87.5 (1)°

Role of ferroptosis and its non-coding RNA regulation in hepatocellular carcinoma

Ferroptosis is a newly discovered form of programmed cell death that involves the accumulation of iron-dependent lipid peroxides and plays a vital role in the tumorigenesis, development, and drug resistance of various tumors such as hepatocellular carcinoma (HCC). As a hotspot in molecular biology, non-coding RNAs (ncRNAs) participate in the initiation and progression of HCC, either act as oncogenes or tumor suppressors. Recent studies have shown that ncRNAs can regulate ferroptosis in HCC cells, which would affect the tumor progression and drug resistance. Therefore, clarifying the underlying role of ferroptosis and the regulatory role of ncRNA on ferroptosis in HCC could develop new treatment interventions for this disease. This review briefly summarizes the role of ferroptosis and ferroptosis-related ncRNAs in HCC tumorigenesis, progression, treatment, drug resistance and prognosis, for the development of potential therapeutic strategies and prognostic markers in HCC patients

1-(2,4-Dinitro­phen­yl)-3,3-dinitro­azetidine

In the title compound, C9H7N5O8, the dihedral angle between the mean plane of the azetidine ring and that of the benzene ring is 26.1 (1)°; the planes of the two nitro groups of the azetidine ring are aligned at 88.7 (1)°

Activation of transient receptor potential vanilloid 1 protects the heart against apoptosis in ischemia/reperfusion injury through upregulating the PI3K/Akt signaling pathway

Transient receptor potential vanilloid 1 (TRPV1) is a nonselective cation channel and a molecular integrator of noxious stimuli. TRPV1 activation confers cardiac protection against ischemia/reperfusion (I/R) injury. The present study aimed to investigate whether the cardioprotective effects of TRPV1 were associated with the inhibition of apoptosis via the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) and extracellular signal-regulated protein kinase 1/2 (ERK1/2) signaling pathways. Briefly, the hearts of TRPV1 knockout (TRPV1-/-) or wild-type (WT) mice were isolated and subjected to 30 min of ischemia followed by 60 min of reperfusion in a Langendorff apparatus in the presence or absence of the PI3K inhibitor, LY294002. At the end of reperfusion, infarct size was measured using 2, 3, 5-triphenyltetrazolium chloride staining and myocardial apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining. The expression levels of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), and phosphorylated Akt and ERK1/2 were determined by western blot analysis. There was a significant increase in the extent of infarction and the percentage of TUNEL-positive cells, and a decrease in the Bcl-2/Bax ratio, and Akt and ERK1/2 phosphorylation in TRPV1-/- hearts. In addition, treatment with LY294002 increased infarct size and the percentage of TUNEL-positive cells, and reduced Bcl-2/Bax expression and Akt phosphorylation in WT hearts, but not in TRPV1-/- hearts, following I/R. Taken together, these data suggested that TRPV1 serves a protective role against myocardial apoptosis during I/R via the PI3K/Akt signaling pathway. In conclusion, activating TRPV1 may be considered a potential approach to protect the heart against I/R injury

Study on the radon adsorption capability of low-background activated carbon

Radon is a significant background source in rare event detection experiments. Activated Carbon (AC) adsorption is widely used for effective radon removal. The selection of AC considers its adsorption capacity and radioactive background. In this study, using self-developed devices, we screened and identified a new kind of low-background AC from Qingdao Inaf Technology Company that has very high Radon adsorption capacity. By adjusting the average pore size to 2.3 nm, this AC demonstrates a radon adsorption capacity of 2.6 or 4.7 times higher than Saratech or Carboact activated carbon under the same conditions.Comment: 21pages, 7 figure

Heterogeneous Multi-agent Zero-Shot Coordination by Coevolution

Generating agents that can achieve zero-shot coordination (ZSC) with unseen partners is a new challenge in cooperative multi-agent reinforcement learning (MARL). Recently, some studies have made progress in ZSC by exposing the agents to diverse partners during the training process. They usually involve self-play when training the partners, implicitly assuming that the tasks are homogeneous. However, many real-world tasks are heterogeneous, and hence previous methods may be inefficient. In this paper, we study the heterogeneous ZSC problem for the first time and propose a general method based on coevolution, which coevolves two populations of agents and partners through three sub-processes: pairing, updating and selection. Experimental results on various heterogeneous tasks highlight the necessity of considering the heterogeneous setting and demonstrate that our proposed method is a promising solution for heterogeneous ZSC tasks

Learning to Coordinate with Anyone

In open multi-agent environments, the agents may encounter unexpected teammates. Classical multi-agent learning approaches train agents that can only coordinate with seen teammates. Recent studies attempted to generate diverse teammates to enhance the generalizable coordination ability, but were restricted by pre-defined teammates. In this work, our aim is to train agents with strong coordination ability by generating teammates that fully cover the teammate policy space, so that agents can coordinate with any teammates. Since the teammate policy space is too huge to be enumerated, we find only dissimilar teammates that are incompatible with controllable agents, which highly reduces the number of teammates that need to be trained with. However, it is hard to determine the number of such incompatible teammates beforehand. We therefore introduce a continual multi-agent learning process, in which the agent learns to coordinate with different teammates until no more incompatible teammates can be found. The above idea is implemented in the proposed Macop (Multi-agent compatible policy learning) algorithm. We conduct experiments in 8 scenarios from 4 environments that have distinct coordination patterns. Experiments show that Macop generates training teammates with much lower compatibility than previous methods. As a result, in all scenarios Macop achieves the best overall coordination ability while never significantly worse than the baselines, showing strong generalization ability