Active planar optical devices that can dynamically manipulate light are highly sought after in modern optics and nanophotonics. The geometric phase derived from the photonic spin-orbit interaction ...provides an integrated strategy. Corresponding elements usually suffer from static functions. Here, we introduce an inhomogeneously self-organized anisotropic medium featured by photo-invertible chiral superstructure to realize geometric phase elements with continuously tunable working spectrum and light-flipped phase profile. Via preprograming the alignment of a cholesteric liquid crystal mixed with a photo-responsive chiral dopant, we demonstrate light-activated deflector, lens, Airy beam and optical vortex generators. Their polychromatic working bands are reversibly tuned in an ultra-broadband over 1000 nm covering green to telecomm region. The chirality inversion triggers facile switching of functionalities, such as beam steering, focusing/defocusing and spin-to-orbital angular momentum conversion. This work offers a platform for advanced adaptive and multifunctional flat optics with merits of high compactness, low loss and broad bandwidth.
Cholesteric liquid crystal (CLC) chiral superstructures exhibit unique features; that is, polychromatic and spin‐determined phase modulation. Here, a concept for digitalized chiral superstructures is ...proposed, which further enables the arbitrary manipulation of reflective geometric phase and may significantly upgrade existing optical apparatus. By encoding a specifically designed binary pattern, an innovative CLC optical vortex (OV) processor is demonstrated. Up to 25 different OVs are extracted with equal efficiency over a wavelength range of 116 nm. The multiplexed OVs can be detected simultaneously without mode crosstalk or distortion, permitting a polychromatic, large‐capacity, and in situ method for parallel OV processing. Such complex but easily fabricated self‐assembled chiral superstructures exhibit versatile functionalities, and provide a satisfactory platform for OV manipulation and other cutting‐edge territories. This work is a vital step towards extending the fundamental understanding and fantastic applications of ordered soft matter.
Digitalized chiral superstructures enable the generation, detection, and demultiplexing of optical vortices in a polychromatic, large‐capacity, and in situ way. Such complex but easily fabricated self‐assembled cholesteric liquid‐crystal superstructures provide a versatile platform for various cutting‐edge territories. This work brings new insights to both fundamental understanding and innovative applications of ordered soft matter.
As a well‐recognized technology for optical data encoding and extracting, holography has faced an ever‐growing pursuit in the miniaturization, multifunctionality, and tunability for today's abundant ...information. Despite infusive achievements in metahologram, simultaneous realization of dynamic tunability and high‐dimensional multiplexing is critical yet lagging behind, which becomes one bottleneck for this emerging frontier. Here, an innovative solution is proposed by integrating the limited penetration depth of light in chiral liquid crystals and their intrinsic stimuli‐responsive characteristics. Based on a photoactive chiral dopant and the asymmetric photopatterning boundary confined self‐organization, light‐activated spectrally tunable, polarization‐ and direction‐dependent holograms are created simultaneously. As a promising example for information technology, an encrypted signal light is demonstrated, where the wavelength, propagation direction, helicity of light, and reaction duration serve as customized keys for information decryption. This work extends the construction of soft hierarchical superstructures and offers a satisfactory and open‐ended scheme for the intelligent holography, inspiring advanced display, security, and communication.
A new strategy for simultaneous realization of dynamic and high‐dimensional multiplexed holography is proposed via light‐directed liquid‐crystalline chiral superstructures. Photoactive, bidirectional, polarization‐ and time‐dependent hologram is demonstrated. An encrypted signal light is further presented and decrypted into customized direction messages. This novel methodology integrates diverse multiplexing schemes into a single device, facilitating advanced display, security, and communication.
Lithium metal is the only anode material that can enable the Li−O2 battery to realize its high theoretical energy density (≈3500 Wh kg−1). However, the inherent uncontrolled dendrite growth and ...serious corrosion limitations of lithium metal anodes make it experience fast degradation and impede the practical application of Li−O2 batteries. Herein, a multifunctional complementary LiF/F‐doped carbon gradient protection layer on a lithium metal anode by one‐step in situ reaction of molten Li with poly(tetrafluoroethylene) (PTFE) is developed. The abundant strong polar C‐F bonds in the upper carbon can not only act as Li+ capture site to pre‐uniform Li+ flux but also regulate the electron configuration of LiF to make Li+ quasi‐spontaneously diffuse from carbon to LiF surface, avoiding the strong Li+‐adhesion‐induced Li aggregation. For LiF, it can behave as fast Li+ conductor and homogenize the nucleation sites on lithium, as well as ensure firm connection with lithium. As a result, this well‐designed protection layer endows the Li metal anode with dendrite‐free plating/stripping and anticorrosion behavior both in ether‐based and carbonate ester‐based electrolytes. Even applied protected Li anodes in Li−O2 batteries, its superiority can still be maintained, making the cell achieve stable cycling performance (180 cycles).
A gradient LiF/F‐doped carbon protection layer with synergistic functions of homogenizing Li+ flux, fast Li+ diffusion ability, and low Li+ diffusion barrier is prepared by a one‐step in situ reaction to solve the challenges relating to unstable lithium anode in Li–O2 batteries, and, as a result, significantly boost the cycling stability of the Li–O2 batteries.
How to identify the influential spreaders in social networks is crucial for accelerating/hindering information diffusion, increasing product exposure, controlling diseases and rumors, and so on. In ...this paper, by viewing the k-shell value of each node as its mass and the shortest path distance between two nodes as their distance, then inspired by the idea of the gravity formula, we propose a gravity centrality index to identify the influential spreaders in complex networks. The comparison between the gravity centrality index and some well-known centralities, such as degree centrality, betweenness centrality, closeness centrality, and k-shell centrality, and so forth, indicates that our method can effectively identify the influential spreaders in real networks as well as synthetic networks. We also use the classical Susceptible–Infected–Recovered (SIR) epidemic model to verify the good performance of our method.
•Each node’s k-shell value is considered as its mass and the shortest path distance between two nodes is viewed as their distance.•A new method based on gravity formula is proposed to identify the influential nodes in complex networks.•Our method yields better performance of identifying the influential nodes than many previous methods.•The method can be further generalized.
Polydatin, a natural product, is detected in many daily diets, such as grape juices and peanut. Autophagy regulation is recognized as a new potential strategy for cancer therapy, and previous studies ...demonstrated that polydatin showed remarkable anti-cancer ability. Nevertheless, the capability of polydatin to induce autophagy and its role in anti-osteosarcoma remains obscure. In this study, we investigated the anticancer effect of polydatin on human osteosarcoma cell line MG-63 and its underlying mechanism. Our results indicated that polydatin significantly inhibited proliferation of MG-63 cells in a dose- and time-dependent manner, and increased their apoptosis and autophagic flux. Further experiments showed that polydatin reduced the expression and phosphorylation (Y705) level of STAT3 (Signal transducer and activator of transcription 3), increased the expression of autophagy-related genes (Atg12, Atg14, BECN1, PIC3K3), and therewith triggered autophagic cell death in MG-63 cells. Of note, the cytotoxicity effect of polydatin was rescued by co-treatment with Colivelin (STAT3 activator), suggesting the dependency of MG-63 cells on STAT3 for survival in this process. Moreover, polydatin-triggered autophagy and apoptosis were remarkably reduced following exposure to autophagy inhibitor 3-methyladenine, while cell viability was increased. In conclusion, these data demonstrated that polydatin induced MG-63 cell death through inducing apoptosis, and autophagy which was mediated via the STAT3 signaling. Therefore, polydatin might be a potential clinical drug in the remedy of osteosarcoma.
Graphic abstract
Gastrointestinal microbiota may be involved in
associated gastric cancer development. The aim of this study was to explore the possible microbial mechanisms in gastric carcinogenesis and potential ...dysbiosis arising from
infection.
Deep sequencing of the microbial 16S ribosomal RNA gene was used to investigate alterations in paired gastric biopsies and stool samples in 58 subjects with successful and 57 subjects with failed anti-
treatment, relative to 49
negative subjects.
In
positive subjects, richness and Shannon indexes increased significantly (both p<0.001) after successful eradication and showed no difference to those of negative subjects (p=0.493 for richness and p=0.420 for Shannon index). Differential taxa analysis identified 18 significantly altered gastric genera after eradication. The combination of these genera into a Microbial Dysbiosis Index revealed that the dysbiotic microbiota in
positive mucosa was associated with advanced gastric lesions (chronic atrophic gastritis and intestinal metaplasia/dysplasia) and could be reversed by eradication. Strong coexcluding interactions between
and
,
,
,
,
were found only in advanced gastric lesion patients, and were absent in normal/superficial gastritis group. Changes in faecal microbiota included increased
after successful
eradication and more upregulated drug-resistant functional orthologs after failed treatment.
infection contributes significantly to gastric microbial dysbiosis that may be involved in carcinogenesis. Successful
eradication potentially restores gastric microbiota to a similar status as found in uninfected individuals, and shows beneficial effects on gut microbiota.
In order to solve the problem of low development efficiency of agricultural mechanization information network system, a design and discussion method of agricultural machinery equipment information ...management and control system is proposed. This paper introduces the technologies required to realize the agricultural machinery operation management control system: Android development technology required to develop mobile phone positioning software, Internet map API for displaying location data, and construction of agricultural machinery resource allocation model for the realization of the scheduling module. Different objective functions are set, and the model results in different situations are obtained through experimental data. The experimental data are in the case of schedulable agricultural machinery, if the target is short-distance short-distance operation, it can save time by 0.16 h, and the existing M1 model is in Changying. Village work, the work end time is about 2.5 hours; M4 and M2 models work in the Xuzhuang Village, and the work end time is about 0.5 h; M3 model works in the Jiangtang Village, and the calculation results for different goals are as follows: M1 model first dispatches short-distance operations; the M3 type is dispatched first for short-distance operations; the M4 type operating in Xuzhuang Village is given priority to dispatch short-distance and short-distance operations. According to the analysis of system requirements, each submodule of the system is designed, including the function description and realization method of the module. The history track query module, mobile phone positioning module, and agricultural machinery scheduling module are introduced in detail. Using the Android development technology required by mobile phone positioning software, the information management of user interface, server system, and database is realized, which provides conditions for the collection of agricultural machinery and equipment information and the generation of information management control.
Pollution by heavy metals limits the area of land available for cultivation of food crops. A potential solution to this problem might lie in the molecular breeding of food crops for phytoremediation ...that accumulate toxic metals in straw while producing safe and nutritious grains. Here, we identify a rice quantitative trait locus we name cadmium (Cd) accumulation in leaf 1 (CAL1), which encodes a defensin-like protein. CAL1 is expressed preferentially in root exodermis and xylem parenchyma cells. We provide evidence that CAL1 acts by chelating Cd in the cytosol and facilitating Cd secretion to extracellular spaces, hence lowering cytosolic Cd concentration while driving long-distance Cd transport via xylem vessels. CAL1 does not appear to affect Cd accumulation in rice grains or the accumulation of other essential metals, thus providing an efficient molecular tool to breed dual-function rice varieties that produce safe grains while remediating paddy soils.
Abstract
Self-assembled architectures of soft matter have fascinated scientists for centuries due to their unique physical properties originated from controllable orientational and/or positional ...orders, and diverse optic and photonic applications. If one could know how to design, fabricate, and manipulate these optical microstructures in soft matter systems, such as liquid crystals (LCs), that would open new opportunities in both scientific research and practical applications, such as the interaction between light and soft matter, the intrinsic assembly of the topological patterns, and the multidimensional control of the light (polarization, phase, spatial distribution, propagation direction). Here, we summarize recent progresses in self-assembled optical architectures in typical thermotropic LCs and bio-based lyotropic LCs. After briefly introducing the basic definitions and properties of the materials, we present the manipulation schemes of various LC microstructures, especially the topological and topographic configurations. This work further illustrates external-stimuli-enabled dynamic controllability of self-assembled optical structures of these soft materials, and demonstrates several emerging applications. Lastly, we discuss the challenges and opportunities of these materials towards soft matter photonics, and envision future perspectives in this field.
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