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Dendrobium huoshanense flowers have been widely used for liver protection in China. This work was aimed to discover the natural products with activity of mitigating alcoholic hepatocyte injury from Dendrobium huoshanense flowers via bioactivity-guided isolation, and to clarify the underlying mechanisms of these natural products. As a result, three flavonoids, 3'-O-methylquercetin-3-O-β-D-galactopyranoside (1), 3'-O-methylquercetin-3-O-β-D-glucopyranoside (2) and quercetin-3-O-β-D-glucopyranoside (3), were firstly isolated from D. huoshanense flowers. Results exhibited that flavonoids 1-3 could enhance the cell viability, decrease the expression of ALT and AST, inhibit the cell apoptosis, alleviate the oxidative stress, and mitigate the inflammatory response of alcohol-induced L02 cells. Mechanism study exhibited that flavonoids 1-3 could increase the expression of Nrf2 as well as its downstream antioxidation genes of alcohol-induced L02 cells, while ML-385 (Nrf2 inhibitor) could abolish the inhibitory effects of 1-3 on alcohol-induced hepatocyte injury. Flavonoids 1-3 could also reduce the phosphorylation levels of IκBα and NF-κB p65 of alcohol-induced L02 cells, while SC75741 (NF-κB inhibitor) could not enhance the inhibitory effects of 1-3 on alcohol-induced L02 cells injury. The data above indicated that flavonoids 1-3 could inhibit alcohol-induced hepatocyte injury, which might be attributed to alleviating oxidative stress and mitigating inflammatory response by activating Nrf2 and inhibiting NF-κB pathways.

Surface finish is one of the most important quality characteristics of titanium implants in the medical field. In this paper, a laser-assisted thermochemical polishing system based on scanning galvanometer was designed and built for the ultrahigh-precision polishing of titanium. The influence of the laser processing parameters and initial surface roughness of the workpiece on the final polishing results were systematically studied, and the polishing mechanisms were discussed. The results show that the final polishing quality was closely related to the laser pulse energy, spot overlapping rate, scanning times, and properties of the material itself but not to the initial surface roughness of the workpiece. In addition, the laser destroyed the passivation layer on the surface of the workpiece, resulting in direct contact between the titanium and etching solution. On the other hand, it induced the generation of a thermo-electromotive force, which caused the electrochemical corrosion on the workpiece surface, accelerating the dissolution of peaks on the surface of the material. The workpiece surface finish was improved because of the difference between the material dissolution rates of the peaks and valleys. Finally, ultrahigh-precision polishing of a commercially pure titanium surface was achieved using the optimized process parameters.

Promoting M1 polarization of tumor-associated macrophages (TAMs) is an effective pathway for malignant tumor therapy. In this study, we aimed to demonstrate whether homogeneous Dendrobium officinale polysaccharide (DOP) could promote M1 polarization of TAMs to inhibit tumor growth, and how it promoted. Results exhibited that DOP could inhibit the tumor growth and promote the M1 polarization of TAMs in tumor-bearing mice. Macrophage depletion and replenishment experiment clearly proved that the inhibitory effect of DOP on tumor growth is dependent on promoting M1 polarization of TAMs. Moreover, we found that DOP could reach tumor microenvironment (TME) and directly bind to TAMs to promote its M1 polarization via targeting toll-like receptor 2 (TLR2) after oral administration. These results clarified that DOP could remarkably inhibit the tumor growth of tumor-bearing mice via directly targeting the TLR2 of TAMs to promote its M1 polarization.

A binary mixture of two acidic organophosphorus extractants, such as 2-ethylhexylphosphonic mono-2-ethylhexyl ester (HEHEHP) and di-2-ethylhexyl phosphoric acid (D2EHPA), is widely employed for the...

Parkinson's disease (PD) is an age-related neurodegenerative disorder without effective treatments. Mesencephalic astrocyte-derived neurotrophic factor (MANF) has been suggested to be capable of protecting against PD by inhibiting endoplasmic reticulum (ER) stress-mediated neuronal apoptosis.This study was aimed to evaluate the antiparkinsonian effect of dendrobine and reveal its underlying mechanisms from the perspective of MANF-mediated ER stress suppression.Behavioral assessments of PD mice as well as LDH/CCK-8 assay in SH-SY5Y cells and primary midbrain neurons were carried out to detect the antiparkinsonian effect of dendrobine. Immunofluorescence, western blot, flow cytometry and shRNA-mediated MANF knockdown were used to determine the apoptosis of dopaminergic neurons and the expressions of ER stress-related proteins for investigating the underlying mechanism of dendrobine.Dendrobine significantly ameliorated the motor performance of PD mice and attenuated the injuries of dopaminergic neurons. Dendrobine could also relieve neuronal apoptosis, up-regulate MANF expression and inhibit ER stress, which were largely abolished by shRNA-mediated MANF knockdown in PD model.Dendrobine might protect against PD by inhibiting dopaminergic neuron apoptosis, which was achieved by facilitating MANF-mediated ER stress suppression. Our study suggested that dendrobine could act as a MANF up-regulator to protect against PD, and provided a potential candidate for exploring etiological agents of PD.

In order to extend the service life of injection mold, the use of laser rust removal was used to repair the surface quality of mold steel in this paper. The surface corrosion of mold steel was removed by using the laser dry cleaning method, then the surface roughness was restored to the initial state to meet the performance requirements of manufacturing. By analyzing the experimental results, the influence of laser energy density, spot overlap rate and scanning times on improving the surface quality of corroded area was obtained. It was shown that when the laser energy density, spot overlap rate and scanning times is 26 J/cm2, 18% and 3 times respectively, the optimum surface roughness of Sa2.32μm can be obtained, which meets the production requirements. Compared with traditional rust removal methods, the laser rust removal of the mold surfaces deserves more extensive research and application due to its advantages of high efficiency, precision and environmentally friendly.

A novel method of laser machining combined with high temperature chemical etching (LMHTCE) was proposed. This novel method can take full advantage of both approaches to drill film holes in an IN718 superalloy without a recast layer or a heat affect zone (HAZ). A solution of hydrochloric acid and sodium nitrate, which minimally reacts with IN718 at room temperature but rapidly reacts under high temperatures, was tested and chosen. Holes drilled in air, water, and chemical solutions by a pulsed laser of 1064 nm were studied, and scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) were employed to detect the morphology of the holes and the elemental distribution in different zones. The holes processed in the chemical solution had fewer defects compared with those in the other two mediums. The defocusing distance parameter was optimized to minimize the hole diameter and taper. When the defocusing distance was 0 μm in the drilling stage and − 60 μm in the high temperature chemical etching stage, a hole with a smaller diameter and taper can be obtained.

With the development of ultra-thin liquid-crystal displays, glass has been adopted to replace polymethyl methacrylate (PMMA) in light guide plates (LGPs). In this study, the backlight unit and conical microstructures of the edge-lit LGP were acquired from a software program, namely, TracePro, and the output light effect of the LGP was simulated. The uniformity could exceed 90% after the optimization of the dot parameters and decreased as the size, depth and cone angle of the dots increased substantially. Experiments were conducted to evaluate the accuracy of the simulation results. The features and cross-section of the dots were measured in detail using a digital microscope. Comparison results demonstrate that optimized laser micromachining technology can be used to process scattering dots on glass LGPs, and the features of the processed scattering dots are consistent with the simulation results.

The improvement of aircraft engine performance resulted in the highly demand of drilling micron-sized holes (

PMMA is widely used to make light guide plates (LGP) of backlight module (BLM), but it is easy to deform at high temperatures, which makes the display effect worse. Due to K9 glass has similar optical properties with PMMA and high temperature-resistance, it is proposed to replace PMMA to make LGP. In this paper, femtosecond laser-etched microstructures and BLM optical performances of K9 glass and PMMA were compared, and it provides that it is feasible to use K9 glass LGP in BLM. The microstructures of LGP are obtained by laser percussion and rotary cutting respectively. It was found that K9 glass has a higher laser-induced damage threshold, ablation threshold, and desired micro-holes morphology than PMMA. Then, the luminance uniformity of K9 glass LGP is 90% by simulation, which is greater than that of PMMA LGP. In the future, this research of K9 glass LGP will improve the quality of liquid crystal display and provide a reference for the development of glass LGP.

The use of variable scattering dots to replace simplex dots is proposed to create an excellent light guide plate. The application of ultrafast laser processing on scattering dots is implemented in this paper, and the uniformity and light utilization are verified by means of simulations and experiments. The performance of these dots depends not only on the density and distribution but also on the specific features of the dots. The concept of a suitable shape and smaller dots with better scattering effects is confirmed. The use of femtosecond laser processing can achieve high-quality microdots with arbitrary features, and parallel beams can ensure the future throughput of microstructure arrays.

Stroke is a major public health concern. The lack of effective therapies heightens the need for new therapeutic targets. Mammalian brain has the ability to rewire itself to restore lost functionalities. Promoting regenerative repair, including neurogenesis and dendritic remodeling, may offer a new therapeutic strategy for the treatment of stroke. Here, we report that interaction of neuronal nitric oxide synthase (nNOS) with the protein postsynaptic density-95 (PSD-95) negatively controls regenerative repair after stroke in rats. Dissociating nNOS–PSD-95 coupling in neurons promotes neuronal differentiation of neural stem cells (NSCs), facilitates the migration of newborn cells into the injured area, and enhances neurite growth of newborn neurons and dendritic spine formation of mature neurons in the ischemic brain of rats. More importantly, blocking nNOS–PSD-95 binding during the recovery stage improves stroke outcome via the promotion of regenerative repair in rats. Histone deacetylase 2 in NSCs may mediate the role of nNOS–PSD-95 association. Thus, nNOS–PSD-95 can serve as a target for regenerative repair after stroke.

Thin (0.20 mm) Fe-6.5 wt.%Si sheets have been successfully fabricated by the continuous rolling method. The designed rolling process parameters, including the initial hot-band grain size, grain size after intermediate annealing, cold rolling reduction, and cold rolling temperature, were selected to control the texture development. Dominant recrystallization η fiber [rolling direction (RD)//\( \left\langle {001} \right\rangle \)] was achieved after high-temperature annealing. The produced Fe-6.5 wt.%Si thin sheets are promising alternatives for use in power electronics because of their magnetic properties from 400 Hz to 40 kHz.

It is a main problem that environment can be polluted by discharge of wastewater containing NH4+, Ca2+ and Na+, when rare earths (REs) are extracted in a saponified system using di-(2-ethylhexyl) phosphoric acid (D2EHPA). Pointing to this problem, the selective separation of Pr(Ⅲ) by liquid–liquid extraction using D2EHPA in the presence of a complexing agent of lactic acid (LA) has been studied. Results are shown that the maximum of separation factor (β) between Pr/Ce is 2.04 and extraction selectivity is also enhanced when compared with that of D2EHPA–HCl system. The thermodynamic function △H is determined as exothermically driven. The cation exchange mechanism is discussed by IR spectra. Thus, the results suggest that highly selective separation and extraction of Pr(Ⅲ) from a Pr/Ce solution is possible, providing a simple and environment-friendly complexing method for extraction-separation rare earths, and promoting the sustainable development in rare earths practices.of Pr(Ⅲ) from a Pr/Ce solution is possible, providing a simple and environment-friendly complexing method for extraction-separation rare earths, and promoting the sustainable development in rare earths practices.

Phosphofructokinase-1 (PFK-1), a major regulatory glycolytic enzyme, has been implicated in the functions of astrocytes and neurons. Here, we report that PFK-1 negatively regulates neurogenesis from neural stem cells (NSCs) by targeting pro-neural transcriptional factors. Using in vitro assays, we found that PFK-1 knockdown enhanced, and PFK-1 overexpression inhibited the neuronal differentiation of NSCs, which was consistent with the findings from NSCs subjected to 5 h of hypoxia. Meanwhile, the neurogenesis induced by PFK-1 knockdown was attributed to the increased proliferation of neural progenitors and the commitment of NSCs to the neuronal lineage. Similarly, in vivo knockdown of PFK-1 also increased neurogenesis in the dentate gyrus of the hippocampus. Finally, we demonstrated that the neurogenesis mediated by PFK-1 was likely achieved by targeting mammalian achaete-scute homologue-1 (Mash 1), neuronal differentiation factor (NeuroD), and sex-determining region Y (SRY)-related HMG box 2 (Sox2). All together, our results reveal PFK-1 as an important regulator of neurogenesis.

Bastnaesite was activated at a temperature, and then the rare earths carbonate of the minerals was leached by HCl solution. When activation temperature was 400°C, activation time was 3h, HCl concentration was 3 mol•L-1, leaching temperature was 90°C, liquid to solid was 20:1, the leaching ratio of rare earths carbonate and rare earths fluoride was 94.6% and 0.07% respectively. The results of XRD and SEM showed that bastnaesite was powdered and coarseness in activation process, which made the leaching of rare earths carbonate by HCl solution become easy. The main components of leaching slag were rare earths fluoride, calcium fluoride and barium sulfate.

The hot bands of non-oriented electrical steel were cold rolled by asymmetric rolling with speed ratio of 1.125 as well as conventional symmetric cold rolling to investigate the effects of cold rolling mode on through-thickness texture variation. Asymmetric rolling shows a marked weakening effect on α fiber (RD//) running from {001} to {112} through sheet thickness, especially at the side contacting with faster roll. Asymmetric rolling increases {111} component while decreases {111} component through sheet thickness except for the surface layers. The through-thickness texture variation due to asymmetric rolling was explained in terms of shear strain distribution.

Given an immersed submanifold x: M m → S n in the unit sphere S n without umbilics, a Blaschke eigenvalue of x is by definition an eigenvalue of the Blaschke tensor of x. x is called Blaschke isoparametric if its Mobius form vanishes identically and all of its Blaschke eigenvalues are constant. Then the classification of Blaschke isoparametric hypersurfaces is natural and interesting in the Mobius geometry of submanifolds. When n = 4, the corresponding classification theorem was given by the authors. In this paper, we are able to complete the corresponding classification for n = 5. In particular, we shall prove that all the Blaschke isoparametric hypersurfaces in S5 with more than two distinct Blaschke eigenvalues are necessarily Mobius isoparametric.

For an immersed submanifold x: M m → S n in the unit sphere S n without umbilics, an eigenvalue of the Blaschke tensor of x is called a Blaschke eigenvalue of x. It is interesting to determine all hypersurfaces in S n with constant Blaschke eigenvalues. In this paper, we are able to classify all immersed hypersurfaces in S m+1 with vanishing Mobius form and constant Blaschke eigenvalues, in case (1) x has exact two distinct Blaschke eigenvalues, or (2) m = 3. With these classifications, some interesting examples are also presented.

To investigate the prevalence of active transport (AT, defined as walking or bicycling for transport) and to explore the association between AT and health outcomes, we conducted a population-based cross-sectional study in Jiangsu, China, where walking and bicycling are still the main modes of transport. In this study, 8400 community residents aged 18 or above were interviewed following a multistage random sampling method (100% response rate). Face-to-face questionnaire survey data, anthropometric measurements, and biochemical data from blood tests were collected. Results show that 49.6% of the subjects, as part of daily transport, actively traveled on average 5.3 days per week, 53.5 minutes per day, and 300.3 minutes per week. There was an inverse correlation between AT and some health outcomes: AT respondents had a higher prevalence of cholesterol disorder; AT respondents who actively travelled every day had a higher risk of diabetes, whilst AT respondents with shorter daily or weekly duration had a lower risk of obesity, central obesity, and cholesterol disorder. Moreover, AT influences more health aspects among urban residents than among rural residents. Findings of this study do not support the notion that AT is beneficial to population health. Further research is needed in determining the negative side effects of AT.

Based on the multi-disciplinary researches, and in terms of the transformation efficiency of surface water to soil water, availability of cropland soil water, crop canopy structure, total irrigation volume needed on a given area, and crop yield, this paper discussed the water-saving mechanisms of intercropping system in improving cropland water use efficiency. Intercropping system could promote the full use of cropland water by plant roots, increase the water storage in root zone, reduce the inter-row evaporation and control excessive transpiration, and create a special microclimate advantageous to the plant growth and development. In addition, intercropping system could optimize source-sink relationship, provide a sound foundation for intensively utilizing resources temporally and spatially, and increase the crop yield per unit area greatly without increase of water consumption, so as to promote the crop water use efficiency effectively.

The H - T magnetic phase diagram and field induced magnetic structure in tetragonal DyCo 2 Si 2 with a two-step metamagnetic process have been determined by magnetization and neutron diffraction experiments using a single crystal as well as specific heat experiment on a polycrystalline sample. Three magnetic phases exist below T N =23 K. A simple antiferromagnetic structure (phase I), with the propagation vector Q 1 =(0, 0, 1) and moments along the c -axis, is stable below 21 K under low field. The intermediate field induced magnetic structure (phase II) is characterized by two additional propagation vectors: i) Q 0 =(0, 0, 0) and ii) Q 2 =(1/2, 1/2, 1/2) which is a sub-harmonics of (1, 1, 1) (≡ Q 1 ) and consists of ferromagnetic (111) planes with the sequence of + + + -. It has a resultant magnetization of half the saturation value, i.e. 5.0 µ B /f.u., at low temperature. Between T N and 21 K, an antiferromagnetic phase (phase III) with an unknown structure appears.

Taking three spring wheat cultivars as test materials, a field experiment was conducted to study the effects of different irrigation treatments on the stomatal conductance of the cultivars during their growth period, with the relationships between the stomatal conductance and the environmental factors analyzed. On the basis of winter irrigation with 1800 m3 x hm(-2) of water, three irrigation treatments, i. e., irrigating three times (T1), two times (T2), and once (T3) during spring wheat growth period, were installed, with 1050 m3 x hm(-2) of irrigation water each time. All irrigation treatments had greater effects on the stomatal conductance, which was decreased with the decreasing times of irrigation, and varied with the cultivars. From jointing stage to florescence, the stomatal conductance in all treatments had the same variation trend, i. e., decreased after an initial increase, and reached the peak at heading stage. After florescence, difference occurred among the treatments. In treatment T1, the stomatal conductance of all test cultivars increased after an initial decrease; in treatment T2, the variation patterns of stomatal conductance differed with cultivars; while in treatment T3, the conductance of all cultivars decreased all along. Among the environmental factors, relative atmospheric humidity had the greatest effects on the stomatal conductance, and their correlation coefficient in treatments T2 and T3 reached significant (0.82) and very significant (0.92* *), respectively. The stomatal regulation mechanism of spring wheat adapting to water deficit in Hexi corridor was of feedback manner.

Utilizing the quasiclassical trajectory method, the product rotational polarization of the reaction N(4S) + D2 → ND + D has been calculated at different collision energies on the DMBE potential energy surface [Poveda LA et al., Phys Chem Chem Phys7:2867, 2005]. The distribution of the angle between k and j′, P(θr), the distribution of dihedral angle denoting k–k′–j′ correlation, P(ϕr), as well as the angular distribution of product rotational vectors in the form of polar plots P(θr, ϕr) are calculated. In addition, the four commonly used polarization-dependent differential cross sections, dσ00/dωt, dσ20/dωt, dσ22+/dωt, and dσ21-/dωt with ωt being the polar coordinates of the product velocity k′, are calculated in the center-of-mass frame. The effects of the collision energy on the product polarization are presented and discussed. In comparison with the result of Yu et al. [Yu YJ et al., Chin Phys B20:123402, 2011], significant isotope effects on the stereodynamics of N(4S) + D2(H2) → ND(H) + D(H) have also been revealed.