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Schematic mechanism of Ganoderma atrum polysaccharide (PSG-1) rebuilding the classically activated (M1) and alternatively activated (M2) macrophage polarization balance.

Dynamic control of motion at the molecular level is a core issue in promoting the bottom-up programmable modulation of sophisticated self-organized superstructures. Self-assembled artificial nanoarchitectures through subtle noncovalent interactions are indispensable for diverse applications. Here, the active solar renewable energy is used to harness cholesteric liquid crystal (CLC) superstructure devices via delicate control of the dynamic equilibrium between the concentrations of molecular motor molecules with opposite handedness. Thus, the spectral position and handedness of a photonic superstructure can be tuned continuously, bidirectionally, and reversibly within the entire working spectrum (from near-ultraviolet to the thermal infrared region, over 2 μm). With these unique horizons, three advanced photoresponsive chiroptical devices, namely, a mirrorless laser, an optical vortex generator, and an encrypted contactless photorewritable board, are successfully demonstrated. The sunlight-fueled chirality inversion prompts facile switching of functionalities, such as free-space optical communication, stereoscopic display technology, and spin-to-orbital angular momentum conversion. Motor-based chiroptic devices with dynamic and versatility controllability, fast response, ecofriendly characteristics, stability, and high efficiency have potential to replace the traditional elements with static functions. The inexhaustible natural power provides a promising means for outdoor-use optics and nanophotonics.

The intelligence, complexity, and diversification of nature is a continuous source of inspiration for humankind. Imitating natural intelligence to devise bionic microrobots with self-regulated features remains an enormous challenge. Herein, we demonstrate a biomimetic soft material that uses light to trigger mechanical motion. This light-sensitive mimosa mimetic film was designed based on liquid crystal elastomers (LCEs) and photoisomerizable azo compounds. To control the bending direction, a predesigned UV-induced gradient polymerization was used. The energy-controlled polymerized film comprises one high-density and one low-density liquid crystal mesogen face. Similar to mimosas, the fabricated films achieved stimuli-responsive actuation, exhibiting shape deformation upon light illumination. The elastic network undergoes reversible shape changes via photochemical trans-cis isomerization of an azo compound in response to a stimulus. In this study, only a small amount of photoisomerizable 1-Hydroxy-n-(4-nitro-azobenzene-4′-oxy)hexane (AZO) was used; however, the domino effect caused a significant reversible actuation. The mesogen density of the top and bottom faces was found to be an important factor for the bending control. This study explores a new way to fabricate films that can bend in controlled directions during light irradiation. This phototunable film is expected to be used for applications in microrobotics and micromachinery.

This study investigates and develops for the first time an electrically tunable liquid-crystal–polymer composite laser with a symmetric sandwich structure. This structure includes two identical pol...

Chameleons, which are among the poikilotherms, can rapidly change color for camouflage, communication and thermoregulation. These cold-blooded animals physiologically shift color through the active tuning of lattices of guanine nanocrystals within a superficial thick layer of dermal iridophores. This active tuning can be described as alternating different refractive indices of nano-reflectors, thereby generating interference of light waves. The self-regulation of the skin behind its dynamic color changing ability makes it the ultimate “biomimetic surface” and a continued source of inspiration. We presented a deformation-color multi-responsive actuator whose response is controlled by delicate light to mimic these adaptive functions. This soft smart material is developed by well-aligned cholesteric liquid crystal elastomers (CLCE). It performs a 185 nm wavelength shift of selective reflection and is switched by reacting to exposure time. Effective optical management is critical for the operation of many modern technologies. These results demonstrate distinctive potential opportunities for LC elastomers to control light, thereby enabling new applications of modern technologies to textiles, optics, and architecture.

Nano- and microscale morphology endows surfaces that play conspicuous roles in natural or artificial objects with unique functions. Surfaces with dynamic regulating features capable of switching the structures, patterns, and even dimensions of their surface profiles can control friction and wettability, thus having potential applications in antibacterial, haptics, and fluid dynamics. Here, a freestanding film with light-switchable surface based on cholesteric liquid crystal networks is presented to translate 2D flat plane into a 3D nanometer-scale topography. The wettability of the interface can be controlled by hiding or revealing the geometrical features of the surfaces with light. This reversible dynamic actuation is obtained through the order parameter change of the periodic cholesteric organization under a photoalignment procedure and lithography-free mode. Complex tailored structures can be used to encrypt tactile information and improve wettability by pre-designing the orientation distribution of liquid crystal director. This rapid switching nano-precision smart surface provides a novel platform for artificial skin, optics, and functional coatings. This article is protected by copyright. All rights reserved.

Self-organized periodic micro/nanostructures caused by stimulus-responsive structural deformation often occur in anisotropic self-assembled supramolecular systems (e.g., liquid crystal systems). However, the long-range orderliness of these structures is often beyond control. In this article, we first demonstrate that a large-area disordered two-dimensional (2D) microgrid chiral structure appears in the cholesteric liquid crystal (CLC) reactive mixture because of the photopolymerization-induced Helfrich deformation effect under exposure to the single UV-laser beam. The result is attributed to the impact of an internal longitudinal strain, which is caused by the pitch contraction of the CLC-monomer region through the continuing compression of the thickening CLC polymer layer adhered on the illuminated substrate of the sample during photopolymerization. The experimental results further show that a one-dimensional (1D) UV-laser interference field can be used to effectively control the postformed 2D microgrid structure to arrange in an orderly manner throughout the large exposed area (an order of centimeter). The optimum ability for controlling the orderliness of the microgrid structure can be achieved if the spacing width of the interference field approximates the periodicity of the postformed 2D microgrids. Several factors, such as the pitch of the CLC mixture and the included angle and intensity of the two interfering laser beams, which influence the orderliness and properties of the 2D microgrid structure, are explored in this study. The result of this research opens a new page to improve the applicability of the Helfrich deformation phenomenon and further provides a reference platform for manipulating, modifying, and even tailoring periodic micro/nanostructures in self-organized supramolecular soft-matter systems for application in advanced optics/photonics.

Glioma is one of the most common brain tumors, suggesting the importance of investigating the molecular mechanism of gliomas. We studied the roles of Ribonucleotide Reductase Regulatory Subunit M2 (RRM2) in glioma. Expressions of RRM2 are higher in glioma tissues evidenced by TCGA data, western blot and immunohistochemistry. RRM2 is negatively correlated with glioma patient's survival. RNA-seq showed that genes involved in apoptosis, proliferation, cell adhesion and negative regulation of signaling were up-regulated upon RNAi-mediated knock-down of RRM2. Cell phenotypes specific for stably knocking down RRM2 were determined using stable transfection in vitro. In an in vivo model, knock-down of RRM2 inhibited tumor growth and caused suppression of AKT and ERK1/2 signalings. Interfering RRM2 also down-regulated the expression of cyclin A, cyclin B1, cyclin D1, Vimentin, and N-cadherin, and elevated E-cadherin expression. Moreover, overexpression of RRM2 failed to increase the expression of cyclin B1, cyclin D1, and N-cadherin when phosphorylation of AKT and ERK1/2 was suppressed by LY294002 or PD98059. These findings indicated that RRM2 is a positive regulator of glioma progression which contributes to the migration and proliferation of glioma cells through ERK1/2 and AKT signalings and might be a novel prognostic indicator for glioma patients.

Orientational structure transitions due to a photoinduced surface anchoring modulation were achieved and investigated in the case of NLC microdroplets placed between glycerol and solid surface. The boundary conditions at NLC-glycerol varied under the light action on the dendromer dopant containing azobenzene terminal fragments. At the same time, the NLC had a strong planar anchoring with the polyimide treated substrate. Numerical simulation of the observed orientational structures in NLC microdroplets were carried out.

Supramolecular β-cyclodextrin (β-CD) was used as a soft template for the fabrication of long silver nanowires. A novel design using self-assembled β-CD for the reduction of silver ions was studied. The concentrations of iron chloride, silver nitrate, and the template were controlling factors for the growth of the silver nanowires. Iron chloride was used to accelerate and facilitate the formation of the silver nanowires and inhibit oxidative etching. However, an excessive concentration of Fe+3 resulted in etching of the silver nanostructures. Furthermore, the silver concentration was another controlling factor. The length of the silver nanowires increased as the concentration of silver cations increased. Nevertheless, an excess concentration of silver cations formed various silver crystalline structures. In this study, the optimal ratio between iron chloride and silver nitrate was determined to be 1:13.3. A maximum length of 20 µm was achieved using a concentration of 0.23 M for the soft template. Moreover, the junction of two growing silver nanowires was observed, forming a long fused nanowire, and some significant boundaries were observed. The observed results were further confirmed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses. X-ray diffraction (XRD) and energy dispersive spectrometer (EDS) analyses were used to indicate the presence of silver and the formation of crystalline materials.

Two sequential transformations of the orientational structure in nematic liquid crystal droplets containing a dendrimer additive (nanosized macromolecules with light-absorbing azobenzene terminal moieties) under light irradiation in the UV–blue spectral range were investigated. The origin of these transitions is in the change of the boundary conditions due to photoisomerization of the dendrimer adsorbed onto the liquid crystal–glycerol interface. It was shown that the photoisomerization processes of dendrimer molecules in a liquid crystal are accompanied by a spatial rearrangement of their azobenzene moieties, which is the key point in the explanation of the observed effects.

A structured broad-band photonic film is fabricated by a novel method using multiple gradient UV-induced polymerization in the presence of cholesteric liquid crystals (CLCs). Here, imprinting and broadening of the reflection band of chiral nematic mesophase cells are achieved via controlled UV polymerization. The intensity gradient of UV light is modified by the distance between UV lamp and sample cell, which affects the polymerization rate and leads to the formation of imprinted helical constructions with different pitches. In this study, a comparison of new design process with traditional UV polymerization process is carried out. After seven cycles of gradient UV polymerization, the imprinted photonic construction exhibited a broadened reflection band and Bragg reflection, even for isotropic materials. Because of this, the reflection bandwidth showed a 70% improvement. Additionally, two stacked imprinted cells with different pitches can reflect incident light with a bandwidth over the visible wavelength range of 480–680 nm. A broad-band photonic polymer film can be imprinted using multiple gradient UV photopolymerization in the presence of CLCs. Forming a UV intensity gradient and controlling the rate of photopolymerization are key factors in broadening the reflection band. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017

Ganoderma atrum polysaccharide (PSG-1), a main polysaccharide from Ganoderma atrum, possesses potent antioxidant capacity and cardiovascular benefits. The aim of this study was to investigate the role of PSG-1 in oxidative stress and apoptosis in human umbilical vein endothelial cells (HUVECs) under anoxia/reoxygenation (A/R) injury conditions. The results showed that exposure of HUVECs to A/R triggered cell death and apoptosis. Administration of PSG-1 significantly inhibited A/R-induced cell death and apoptosis in HUVECs. PSG-1-reduced A/R injury was mediated via mitochondrial apoptotic pathway, as evidenced by elevation of mitochondrial Bcl-2 protein and mitochondrial membrane potential, and attenuation of Bax translocation, cytochrome c release and caspases activation. Furthermore, PSG-1 enhanced the activities of superoxide dismutase, catalase and glutathione peroxidase and glutathione content, and concomitantly attenuated reactive oxygen species generation, lipid peroxidation and glutathione disulfide content. The antioxidant, N-acetyl-l-cysteine, significantly ameliorated all of these endothelial injuries caused by A/R, suggesting that antioxidant activities might play a key role in PSG-1-induced endothelial protection. Taken together, these findings suggested that PSG-1 could be as a promising adjuvant against endothelial dysfunction through ameliorating oxidative stress and apoptosis.

Mono- and bis-rhodamine derivatives appended with amino (RhB1) and imino (BRI) groups, respectively, have been designed as colorimetric and fluorescent sensors for the selective detection of Pd2+. In addition, an attempt has been made to improve the water solubility of the probe by synthesizing inclusion complexes of RhB1 with β-cyclodextrin as the host molecule. The resulting probe, RhB1-CD, exhibited exactly the same physicochemical phenomena as the guest molecule RhB1, indicating that complexation with β-CD improved the water solubility of RhB1 without affecting its sensing ability. With increasing concentrations of Pd2+, the absorption (556 nm) and emission (591 nm) intensities of BRI as well as the absorption intensities of RhB1/RhB1-CD (563 nm) increase, whereas the emission intensities of RhB1/RhB1-CD decrease due to fluorescence quenching. Therefore, BRI can act as an "OFF-ON" fluorescent probe switch in CH3CN/H2O (3 : 2 v/v) with a detection limit of 1 μM in solution, whereas RhB1 and RhB1-CD act as "ON-OFF" fluorescent probes in EtOH/H2O (1 : 1 v/v) and water, respectively, with a detection limit of 10 μM. All these probes exhibited high selectivity for Pd2+ and reversibility by treatment with Na2S. In the presence of commonly coexisting metal ions, such as Hg2+, Fe3+, Cu2+ and Al3+, BRI undergoes either catalytic Schiff base hydrolysis or it is unaffected by its affinity to the metal ions. However, Pd2+ can be effectively distinguished by a 12-15 nm bathochromic shift in its emission spectrum when compared with that of other metal ions. A Job's plot revealed that BRI forms 1 : 2 complexes by a spirolactam ring opening mechanism, whereas RhB1/RhB1-CD form 2 : 1 complexes by a ring opening mechanism followed by Pd2+-induced dimerization; the proposed binding mechanisms are presented.

Two structurally isomeric azobenzene- and cholesteryl-based derivatives with varying alkyl chain lengths were developed as ALS-type gelators (N2 and N4) and synthesized and characterized spectroscopically. Of the two, N4 acted as a more efficient gelator than N2 since N4 could gel a larger number of solvents. The critical gelation concentration (CGC) of N4 was found to be less than that of N2 in the same solvent system. The morphological analyses of both gelators using SEM and TEM revealed that N4 exhibited self-assembled fibrous structures, whereas N2 exhibited spherical nanoparticles. The van der Waals interactions between the cholesteryl units, hydrogen bonding between the amide linkages and π–π stacking between the azobenzene units provided the driving force for the aggregation and gel formation. These driving forces were evidenced by temperature dependent 1H-NMR, FTIR and XRD analyses. Increasing the temperature of the gels shifted (upfield and downfield) the protons in the 1H-NMR spectra as well as the absorption bands in the FTIR spectra indicating that the intermolecular forces between the molecules became disrupted and caused gel → sol transitions. These transitions were reversible after cooling to room temperature. Similarly, the gel → sol transitions could be triggered by UV light (due to trans/cis isomerization); however, the transition was irreversible in the presence of visible light due to the formation of the more stable cis isomer. Hence, the gel state could be retained by heating and cooling the cis-conformation. In addition, the length of the molecule as determined by simulation software was found to match the values observed from the XRD analysis, and the interlayer distances were found to be 1.78 and 1.85 nm for N2 and N4, respectively. Based on this evidence, an aggregation mechanism was proposed. The differential scanning calorimetry (DSC) and polarized optical microscopy (POM) results revealed that both gelators exhibited grainy nematic mesophase textures during the heating and cooling cycles. These gelators underwent phase-selective gelation in the solvent mixtures containing gelling and nongelling solvents, which demonstrated the applicability of these gelators for the separation and purification of solvents.

Liquid crystals (LCs) are distinctive materials that are applicable to a wide range of disciplines, such as continuum mechanics, optics of anisotropic media, statistical physics, and crystallography. The diverse structures and eye-catching topological defects of LCs in confined geometries are affected by nematic elasticity, chirality, and surface anchoring. Herein, we report the formation and detailed configuration of cholesteric LC (CLC) microdroplets with different pitches pierced by electrospun poly(methyl methacrylate) microfibers. Two kinds of surface anchoring, namely, homeotropic anchoring at the air–CLC droplet interface and planar anchoring at the fiber–CLC droplet interface, coexist in this system. By controlling temperature and light irradiation, the system exhibits thermal- and photo-dependent LC morphological and topological evolutions. The observed structures are complemented by numerical simulations of possible director fields decorated by defects. The externally controllable CLC necklaces constitute extraordinary systems for exploring the morphology and topological defects and open a route for applications in topological remote control, nanoscience, biomedical research, and the development of devices based on topologically structured soft media.

Three high-resonance core compounds, BHC-6, BHC-11 and BHC-cho , were synthesized. The morphologies of the self-assembled xerogels of the synthesized compounds were studied using SEM and TEM. The molecular interactions and the formation of asymmetric constructions were investigated using temperature-dependent 1 H NMR spectroscopy and circular dichroism spectrometry, respectively. The induction of an asymmetric helical structure was further confirmed using TEM. The results show that increasing the resonance length strengthens intermolecular forces, leading to the formation of gels. A chiral environment produces a steric field effect, leading to the formation of asymmetric constructions. The interactions between functional groups were further confirmed using 2D nuclear overhauser effect spectroscopy NMR. The reversible E – Z isomerization and dimer formation of cinnamoyl derivatives were investigated using UV–vis and fluorescence spectrometry, relatively.

A liquid crystal elastomer (LCE) film is successfully deposited with a terahertz metamaterial using thermal evaporation via a programmed electronic shutter and high-efficiency cooling system. The transmittance of the metamaterial at its resonance frequency is monotonically increased from 0.0036 to 1.0 as a pump beam bends the LCE film, so the metamaterial has a large switching contrast of 277 at the frequency. The monotonic increase in the resonance transmittance arises from the constant resonance frequency of the metamaterial at the transmittance modulation and depicts that the metamaterial-deposited LCE film can continuously tune the transmitted intensity of a terahertz beam. The metamaterial-deposited LCE film has potential in developing continuously tunable intensity modulators with large switching contrasts for the application of terahertz imaging and terahertz communication. Therefore, the thermal evaporation expands the application of metamaterials and improves their optical properties.

To investigate the computed tomography (CT) imaging and pathological basis of the linear shadows connecting pulmonary segmental arteries to horizontal fissure (hereinafter referred to as “linear shadow”) on thin-slice CT. Collect 127 clinical cases to analyze the display and morphology of linear shadows on the thin-slice CT and to measure their length, thickness, and angle. Collect 11 autopsy specimens of coal worker's pneumoconiosis to conduct an imaging and pathology basis control study for the linear shadows. There is no correlation between the linear shadow and gender, age, and smoking history. Linear shadows are observed in 54.33% of patients. 93.33% of those linear shadows are straight lines. Generally, the lengths are less than 10 mm, the thicknesses are around 1 mm, and the scopes of angles are wide, range from acute angles to obtuse angles. The linear shadow is a banded structure consisting of loose connective tissue, small blood vessels, and small lymphatic vessels due to the visceral pleura recessed and fused into the lung. Linear shadows are intrinsic to the lung. The linear shadows consist of loose connective tissue, small blood vessels, and small lymphatic vessels.

An infrared (IR) reflector that has ultra-wide reflection band and high reflectance was successfully fabricated based on an enantiomorphic chiral polymer composite template-made method involving UV-curing, washing-out, stacking, and refilling. In this study, an IR reflector reflecting >80% of incoming solar IR light from 800 nm to 1500 nm and retaining acceptable transmittance in the visible region is demonstrated. This undertaking is achieved by stacking two enantiomorphic double-polymerized chiral polymer templates with large longitudinal pitch gradients as a composite template cell designed for the near-IR region. Heat insulation test reveals that the temperature can be effectively lowered by 2 °C–3 °C by using the IR reflector, thereby indicating that a considerable amount of incident heat could be isolated and a significant amount of energy could be saved by cooling. The sample has potential in green and military applications, such as energy-saving green windows and anti-IR devices.

Glioma has been considered as one of the most aggressive and popular brain tumors of patients. It is essential to explore the mechanism of glioma. In this study, we established PSMB8 as a therapeutic target for glioma treatment. Expression of PSMB8 as well as Ki-67 was higher in glioma tissues demonstrated by western blot and immunohistochemistry. Then, the role of PSMB8 in migration and proliferation of glioma cells was investigated by conducting wound-healing, trans-well assay, cell counting kit (CCK)-8, flow cytometry assay and colony formation analysis. The data showed that interfering PSMB8 may inhibit the migration and proliferation of glioma cells by reducing expression of cyclin A, cyclin B1, cyclin D1, Vimentin, and N-cadherin, and by increasing expression of E-cadherin. Additionally, interfering PSMB8 may induce apoptosis of glioma cells by upregulating caspase-3 expression. Furthermore, these in vitro findings were validated in vivo and the ERK1/2 and PI3k/AKT signaling pathways were involved in PSMB8-triggered migration and proliferation of glioma cells. In an in vivo model, downregulation of PSMB8 suppressed tumor growth. In conclusion, PSMB8 is closely associated with migration, proliferation, and apoptosis of glioma cells, and might be considered as a novel prognostic indicator in patients with gliomas.

The effect of carrot juice fermented with Lactobacillus plantarum NCU116 on high-fat and low-dose streptozotocin (STZ)-induced type 2 diabetes in rats was studied. Rats were randomly divided into five groups: non-diabetes mellitus (NDM), untreated diabetes mellitus (DM), DM plus L. plantarum NCU116 (NCU), DM plus fermented carrot juice with L. plantarum NCU116 (FCJ), and DM plus non-fermented carrot juice (NFCJ). Treatments of NCU and FCJ for 5 weeks were found to favorably regulate blood glucose, hormones, and lipid metabolism in the diabetic rats, accompanied by an increase in short-chain fatty acid (SCFA) in the colon. In addition, NCU and FCJ had restored the antioxidant capacity and morphology of the pancreas and kidney and upregulated mRNA of low-density lipoprotein (LDL) receptor, cholesterol 7α-hydroxylase (CYP7A1), glucose transporter-4 (GLUT-4), peroxisome proliferator-activated receptor-α (PPAR-α), and peroxisome proliferator-activated receptor-γ (PPAR-γ). These results have for the first time demonstrated that L. plantarum NCU116 and the fermented carrot juice had the potential ability to ameliorate type 2 diabetes in rats.

Methane explosion pressure characteristics under the condition of different temperatures (25°C-200 °C) were studied by the special environment 20L explosion characteristics test system. By the experimental results, in the case of other conditions unchanged, with the increase of environmental temperature, the maximum explosion pressure of the optimum explosion concentration decrease, the maximum explosion pressure and the reciprocal of environmental temperature show linear attenuation law, the maximum pressure rise rate is not influenced by environmental temperature basically; Outside the scope of explosion limits at normal temperature and pressure, with the increase of environmental temperature, no explosion methane-air mixture are explosive gradually, the maximum explosion pressure and maximum pressure rise rate are in the relationship of different exponential growth with the increase of ambient temperature. The conclusions provide an important theoretical basis for prevent mine gas explosion accidents and coal bed methane safely use.

The composition and microstructure of nanocrystalline soft magnetic materials with different components were analyzed and calculated in detail by using the method of micro-structural analysis and thermal magnetic analysis. The results show that the micro-structural parameters of the nanocrystalline soft magnetic materials are closely related to their chemical composition. The internal mechanism of the chemical composition affecting on the micro-structural parameters were explained by the crystallization process of amorphous materials and the phase transition kinetics, respectively.

In order to meet the trend for flight test technology, this paper presents a monitoring expert system of flight parameters based on embedded technology , which can achieve real-time interpretation of flight data air and provide the parameters for the AHRS, engines, flight controls for aircraft crew members as well as the disposal of the special circumstances operating. It can be used for real-time collection and record a variety of digital information, control information and video information transmitting by the missiles and fiber during the fly testing process.

The new Nd-Fe-B magnets were prepared by powder metallurgical processing. The thermal stability and magnetic properties were found to be remarkably improved after annealing at 680 °C for 2 h. The Br, and Hc, BH of annealed magnets were improved by-0.04 T, 132 KA·m-1, 22 KJ·m-3, from 1.25 T, 882 KA·m-1, 286 KJ·m-3 of the as-sintered magnets, respectively. The losses and average temperature coefficients of magnetic properties were very low at 373 K. Compare with the as-sintered magnets, the magnetic property losses of the annealed magnets decreased by half at different temperature. Scanning electron microscopy on magnets did reveal a noticeable difference in phase morphology, and found that the improvements of thermal stability and magnetic properties can be attributed to the change of magnetic domain wall motion, composition, stray demagnetizing fields, and microstructure. The new Nd-Fe-B preferment magnets are promising to use in the all-electric bus hub direct drive motor.