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The authors prove the long time stability of KAM tori (thus quasi-periodic solutions) for nonlinear Schrödinger equation \\sqrt{-1}\\, u_{t}=u_{xx}-M_{\\xi}u+\\varepsilon|u|^2u, subject to Dirichlet boundary conditions u(t,0)=u(t,\\pi)=0, where M_{\\xi} is a real Fourier multiplier. More precisely, they show that, for a typical Fourier multiplier M_{\\xi}, any solution with the initial datum in the \\delta-neighborhood of a KAM torus still stays in the 2\\delta-neighborhood of the KAM torus for a polynomial long time such as |t|\\leq \\delta^{-\\mathcal{M}} for any given \\mathcal M with 0\\leq \\mathcal{M}\\leq C(\\varepsilon), where C(\\varepsilon) is a constant depending on \\varepsilon and C(\\varepsilon)\\rightarrow\\infty as \\varepsilon\\rightarrow0.

Over 60 years of spacecraft exploration has revealed that the Earth’s Moon is characterized by a lunar crust 1 dominated by the mineral plagioclase, overlying a more mafic (richer in iron and magnesium) mantle of uncertain composition. Both crust and mantle formed during the earliest stages of lunar evolution when late-stage accretional energy caused a molten rock (magma) ocean, flotation of the light plagioclase, sinking of the denser iron-rich minerals, such as olivine and pyroxene, and eventually solidification 2 . Very large impact craters can potentially penetrate through the crust and sample the lunar mantle. The largest of these craters is the approximately 2,500-kilometre-diameter South Pole-Aitken (SPA) basin 3 on the lunar far side. Evidence obtained from orbiting spacecraft shows that the floor of the SPA basin is rich in mafic minerals 4 , but their mantle origin is controversial and their in situ geologic settings are poorly known. China’s Chang’E-4 lunar far-side lander recently touched down in the Von Kármán crater 5 , 6 to explore the floor of the huge SPA basin and deployed its rover, Yutu-2. Here we report on the initial spectral observations of the Visible and Near Infrared Spectrometer (VNIS) 7 onboard Yutu-2, which we interpret to represent the presence of low-calcium (ortho)pyroxene and olivine, materials that may originate from the lunar mantle. Geological context 6 suggests that these materials were excavated from below the SPA floor by the nearby 72-km-diameter Finsen impact crater event, and transported to the landing site. Continued exploration by Yutu-2 will target these materials on the floor of the Von Kármán crater to understand their geologic context, origin and abundance, and to assess the possibility of sample-return scenarios. Initial spectral observations by China’s Chang’E-4 far-side lunar rover suggest the presence of materials that may originate from the Moon’s mantle.

Active electronic states in transition metal dichalcogenides are able to prompt hydrogen evolution by improving hydrogen absorption. However, the development of thermodynamically stable hexagonal 2H-MoS 2 as hydrogen evolution catalyst is likely to be shadowed by its limited active electronic state. Herein, the charge self-regulation effect mediated by tuning Mo−Mo bonds and S vacancies is revealed in metastable trigonal MoS 2 (1T'''-MoS 2 ) structure, which is favarable for the generation of active electronic states to boost the hydrogen evolution reaction activity. The optimal 1T'''-MoS 2 sample exhibits a low overpotential of 158 mV at 10 mA cm −2 and a Tafel slope of 74.5 mV dec −1 in acidic conditions, which are far exceeding the 2H-MoS 2 counterpart (369 mV and 137 mV dec −1 ). Theoretical modeling indicates that the boosted performance is attributed to the formation of massive active electronic states induced by the charge self-regulation effect of Mo−Mo bonds in defective 1T'''-MoS 2 with rich S vacancies. Metal chalcogenides have shown promising performances for renewable hydrogen evolution and such activities are sensitive to the material electronic structures. Here, authors modulate the electronic properties of molybdenum sulfide in 1T'''-MoS 2 for hydrogen evolution electrocatalysis.

With the continuous development of social economy, information resources have become more and more valued resources. Based on the intelligent monitoring architecture of the multimedia sensor network, this article proposes a nonline-of-sight positioning method that can fit the characteristics of autonomous movement for the object of intelligent terminal, that is, first draw the corresponding position trajectory according to the speed attribute of the node. On this basis, according to the relative position trajectory and radio frequency signal positioning, the two-by-two positioning of position and direction is comprehensively realized, and the positioning result is obtained; the positioning accuracy is evaluated according to the positioning of the radio frequency signal, and the false positioning result of the distorted radio frequency signal is stripped out to reduce the error influences. Practical results show that the method is effective and can meet the needs of positioning accuracy.

Background Colon cancer is the second leading cancer worldwide. Recurrent disease and chemotherapeutic drug resistance are very common in the advanced stage of colon cancer. ATP-citrate lyase (ACLY), the first-step rate-controlling enzyme in lipid synthesis, is elevated in colon cancer. However, it remains unclear about the exact role of ACLY in the development of colon cancer metastasis. Methods To evaluate the role of ACLY in colon cancer metastasis, we performed cell migration and invasion assays in two ACLY-deficient colon cancer cell lines. Colon cancer mouse model is used to examine ACLY’s effects on colon metastasis potentials in vivo. We analyzed the correlation between ACLY and CTNNB1 protein in 78 colon cancer patients by Pearson correlation. To finally explore the relationship of ACLY and CTNNB1, we used western blots, migration and invasion assays to confirm that ACLY may regulate metastasis by CTNNB1. Results Our data showed that the abilities of cell migration and invasion were attenuated in ACLY-deficient HCT116 and RKO cell lines. Furthermore, we describe the mechanism of ACLY in promoting colon cancer metastasis in vitro and in vivo. ACLY could stabilize CTNNB1 (beta-catenin 1) protein by interacting, and the complex might promote CTNNB1 translocation through cytoplasm to nucleus, subsequently promote the CTNNB1 transcriptional activity and migration and invasion abilities of colon cancer cells. Immunohistochemical analysis of 78 colon cancer patients showed that the high expression levels of ACLY and CTNNB1 protein was positively correlated with metastasis of colon cancer. Conclusions These results shed new light on the molecular mechanism underlying colon cancer metastasis, which might help in improving therapeutic efficacy.

In this paper, a terahertz (THz) biosensor based on all-metal metamaterial is theoretically investigated and experimentally verified. This THz metamaterial biosensor uses stainless steel materials that are manufactured via laser-drilling technology. The simulation results show that the maximum refractive index sensitivity and the figure of merit of this metamaterial sensor are 294.95 GHz/RIU and 4.03, respectively. Then, bovine serum albumin was chosen as the detection substance to assess this biosensor’s effectiveness. The experiment results show that the detection sensitivity is 72.81 GHz/(ng/mm2) and the limit of detection is 0.035 mg/mL. This THz metamaterial biosensor is simple, cost-effective, easy to fabricate, and has great potential in various biosensing applications.

PurposeImmunotherapy aimed at inhibiting the PD-1/PD-L1 immune checkpoint has been approved and used successfully for the treatment of bladder cancer. The identification of markers predictive of response to immune checkpoint inhibitors is critical to advancing the success of this therapy. 18F-FDG PET/CT is a molecular imaging technique that can provide phenotypic information on malignant tumours. It is currently unknown whether there is a relationship between 18F-FDG uptake and expression of PD-1/PD-L1 in bladder cancer. In this study, we investigated whether PD-1/PD-L1 expression is associated with 18F-FDG uptake in bladder cancer, and whether 18F-FDG PET/CT imaging can be used to predict the PD-1/PD-L1 status of bladder cancer.MethodsA retrospective analysis was performed in 63 patients with bladder cancer who had undergone 18F-FDG PET/CT before surgical resection. Maximum standardized uptake values (SUVmax) were determined.ResultsSUVmax was significantly higher in PD-1-positive patients than in PD-1-negative patients (33.0 ± 13.9 and 19.6 ± 14.2, respectively; P = 0.032), and in PD-L1-positive patients than in PD-L1-negative patients (29.1 ± 15.6 and 15.8 ± 11.4, respectively; P < 0.0001). In a multivariate analysis SUVmax was significantly associated with both PD-1 expression and PD-L1 expression (P = 0.021 and P = 0.003, respectively). Using a SUVmax cut-off value of 22.7, PD-1 status and PD-L1 status could be predicted with accuracies of 71.4% and 77.8%, respectively.ConclusionHigher 18F-FDG uptake by bladder cancer is associated with elevated PD-1/PD-L1 expression. 18F-FDG PET/CT may be useful for predicting the PD-1/PD-L1 status of bladder cancer and for determining the optimal therapeutic strategy.

The quality of traditional Chinese herbal medicine, which plays a very important role in the health system of China, is determined by the active substances produced by the plants. The type, content, and proportion of these substances may vary depending on ecological factors in areas where the plants are grown. Sinopodophyllum hexandrum (Royle) T.S. Ying, an endangered plant species with great medical value, was investigated in eight production locations representative of its natural geographical distribution range in China. The correlation between the contents of the active ingredients extracted from the roots and rhizomes of S. hexandrum and the ecological factors were evaluated step-by-step using a series of computational biology methodologies. The results showed that ecological factors had significant effects on the contents but not on the types of the active ingredients in eight production locations. The primary ecological factors influencing the active substances included the annual average precipitation, July mean temperature, frost-free period, sunshine duration, soil pH, soil organic matter, and rapidly available potassium in the soil. The annual average precipitation was the most important determinant factor and was significantly and negatively correlated with the active ingredient contents (P < 0.001). In contrast, organic matter was the most important limiting factor and was significantly and positively correlated with the active substances. These ecological factors caused 98.13% of the total geographical variation of the active ingredient contents. The climate factors contributed more to the active ingredient contents than did the soil factors. It was concluded that from the view of the contents of the secondary metabolites and ecological factors of each growing location, in Jingyuan, Ningxia Province, and Yongdeng, Gansu Province, conditions were favorable to the production of podophyllotoxin and lignans, whereas in Shangri-La, Yunnan Province, and Nyingchi, Tibet, conditions were favorable to the production of quercetin and kaempferol.

The intrinsic activity of in-plane chalcogen atoms plays a significant role in the catalytic performance of transition metal dichalcogenides (TMDs). A rational modulation of the local configurations is essential to activating the in-plane chalcogen atoms but restricted by the high energy barrier to break the in-plane TM-X (X = chalcogen) bonds. Here, we theoretically design and experimentally realize the tuning of local configurations. The electron transfer capacity of local configurations is used to screen suitable TMDs materials for hydrogen evolution reaction (HER). Among various configurations, the triangular-shape cobalt atom cluster with a central sulfur vacancy (3Co Mo - V S ) renders the distinct electrocatalytic performance of MoS 2 with much reduced overpotential and Tafel slope. The present study sheds light on deeper understanding of atomic-scale local configuration in TMDs and a methodology to boost the intrinsic activity of chalcogen atoms. Designing and realizing local configurations can activate the in-plane chalcogen atoms of transition metal dichalcogenide to enhance the HER activity. We combine the theoretical screening (charge transfer capability) and experimental realization to achieve highly active local configurations

HighlightsHigh-performance Zn||I2 batteries were established by coating zeolite protecting layers.The Zn2+-conductive layer suppresses I3− shuttling, Zn corrosion/dendrite growth.The Zeolite-Zn||I2 batteries achieve long lifespan (91.92% capacity retention after 5600 cycles), high coulombic efficiencies (99.76% in average) and large capacity (203–196 mAh g−1 at 0.2 A g−1) simultaneously.The intrinsically safe Zn||I2 battery, one of the leading candidates aiming to replace traditional Pb-acid batteries, is still seriously suffering from short shelf and cycling lifespan, due to the uncontrolled I3−-shuttling and dynamic parasitic reactions on Zn anodes. Considering the fact that almost all these detrimental processes terminate on the surfaces of Zn anodes, modifying Zn anodes’ surface with protecting layers should be one of the most straightforward and thorough approaches to restrain these processes. Herein, a facile zeolite-based cation-exchange protecting layer is designed to comprehensively suppress the unfavored parasitic reactions on the Zn anodes. The negatively-charged cavities in the zeolite lattice provide highly accessible migration channels for Zn2+, while blocking anions and electrolyte from passing through. This low-cost cation-exchange protecting layer can simultaneously suppress self-discharge, anode corrosion/passivation, and Zn dendrite growth, awarding the Zn||I2 batteries with ultra-long cycle life (91.92% capacity retention after 5600 cycles at 2 A g−1), high coulombic efficiencies (99.76% in average) and large capacity (203–196 mAh g−1 at 0.2 A g−1). This work provides a highly affordable approach for the construction of high-performance Zn-I2 aqueous batteries.