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Ti-Al alloyed coatings with different Nb doping contents were fabricated on TC4 titanium alloy by laser surface alloying to improve high temperature oxidation resistance of the alloy. Structures and high temperature oxidation behaviors of the alloyed coatings were analyzed and tested by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and box-type resistance furnace. The results show that the alloyed coatings consist of TiAl and Ti3Al, and no niobium compound are formed in Ti-Al-Nb alloyed coatings. The alloyed coatings are uniform and exhibit excellent metallurgical bonding with the substrates. A large amount of surface cracks and a few penetrating cracks are formed in Ti-Al alloyed coating without Nb doping, while no obvious cracks are formed in Ti-Al alloyed coating with Nb doping. The oxidation mass gains of all the alloyed coatings were significantly lower than those of the substrate. The alloyed coatings with Nb doping exhibit more excellent high temperature oxidation resistance due to the beneficial machanism of Nb doping. The mechanism of Nb doping on improving high temperature oxidation resistance of Ti-Al alloyed coatings includes reducing the defect concentration of TiO2, refining oxide grains and promoting the formation of Al2O3.

Background: 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.Purpose: 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.Methods: 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.Results: 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.Conclusion: 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. [ABSTRACT FROM AUTHOR]

Quasiclassical trajectory (QCT) calculations have been performed for the abstraction reaction, D' + DS(v = 0, j = 0) → D'D + S on a new LZHH potential energy surface (PES) of the adiabatic ³A" electronic state [Lü et al. 2012 J. Chem. Phys. 136 094308]. The collision energy effect on the integral cross section and product polarization are studied over a wide collision energy range from 0.1 to 2.0 eV. The cross sections calculated by the QCT procedure are in good accordance with previous quantum wave packet results. The three angular distribution functions, P(ϑr, φr), and P(ϑr), P(φr), together with the four commonly used polarization-dependent differential cross sections ((2π/σ) (dσ00/dωt), (2π/σ)(dσ00)(dωt), (2π/σ)(dσ20)(dωt), (2π/σ)(dσ22)(dωt), (2π/σ)(dσ21-/dωt), are obtained to gain insight into the chemical stereodynamics of the title reaction. Influences of the collision energy on the product polarization are exhibited and discussed. [ABSTRACT FROM AUTHOR]

Utilizing the quasiclassical trajectory method, the product rotational polarization of the reaction has been calculated at different collision energies on the DMBE potential energy surface [Poveda LA et al., Phys Chem Chem Phys 7:2867, 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 B 20:123402, 2011], significant isotope effects on the stereodynamics of have also been revealed. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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·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·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. [ABSTRACT FROM AUTHOR]

Ganoderma lucidum , a renowned tonic traditional Chinese medicine, is widely recognized for the exceptional activity in soothing nerves and nourishing the brain. It has been extensively employed to alleviate various neurological disorders, notably Parkinson's disease (PD). To appraise the antiparkinsonian effect of GAA, the main bioactive constituent of G. lucidum, and clarify the molecular mechanism through the perspective of ferritinophagy-mediated dopaminergic neuron ferroptosis. PD mouse and cell models were established using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 1-methyl-4-phenylpyridinium (MPP+), respectively. Cell viability, behavioral tests and immunofluorescence analysis were performed to evaluate the neurotoxicity, motor dysfunction and dopaminergic loss, respectively. Biochemical assay kits were used to determine the levels of iron, lipid reactive oxygen species (ROS), malondialdehyde (MDA), total ROS and glutathione (GSH). Western blot and immunofluorescence were applied to detect the expressions of nuclear receptor co-activator 4 (NCOA4), ferritin heavy chain 1 (FTH1), p62 and LC3B. Additionally, NCOA4-overexpressing plasmid vector was constructed to verify the inhibitory effect of GAA on the neurotoxicity and ferroptosis-related parameters in PD models. GAA significantly mitigated MPP+/MPTP-induced neurotoxicity, motor dysfunction and dopaminergic neuron loss (p ＜0.01 or p ＜0.05). In contrast to MPP+/MPTP treatment, GAA treatment decreased the levels of iron, MDA, lipid and total ROS, while increasing the GSH level. GAA also reduced the levels of NCOA4 and LC3B, and enhanced the expressions of FTH1 and p62 in PD models (p ＜0.01 or p ＜0.05). However, the protective effect of GAA against the neurotoxicity, NCOA4-mediated ferritinophagy and ferroptosis in PD model was abolished by the overexpression of NCOA4 (p ＜0.01). GAA exerted a protective effect on PD, and this effect was achieved by suppressing dopaminergic neuron ferroptosis through the inhibition of NCOA4-mediated ferritinophagy. [Display omitted] • GAA alleviates MPP+-induced neurotoxicity in vitro. • GAA mitigates MPTP-induced motor dysfunction and dopaminergic neurons loss in vivo. • GAA inhibits MPP+/MPTP-induced neurons ferroptosis in vitro and in vivo. • GAA inhibits MPP+/MPTP-induced neurons ferritinophagy in vitro and in vivo. • GAA suppresses NCOA4-mediated ferritinophagy to inhibit dopaminergic neuron ferroptosis to alleviate PD. [ABSTRACT FROM AUTHOR]

An amyloid-β (Aβ) fibril is a vital pathogenic factor of Alzheimer's disease (AD). Aβ fibril disintegrators possess great potential to be developed into novel anti-AD agents. Here, a ligand fishing method was employed to rapidly discover Aβ 42 fibril disintegrators from Ganoderma lucidum using Aβ 42 fibril-immobilized magnetic beads, which led to the isolation of six Aβ 42 fibril disintegrators including ganodermanontriol, ganoderic acid DM, ganoderiol F, ganoderol B, ganodermenonol, and ergosterol. Neuroprotective evaluation in vitro exhibited that these Aβ 42 fibril disintegrators could significantly mitigate Aβ 42 -induced neurotoxicity. Among these six disintegrators, ergosterol and ganoderic acid DM with stronger protecting activity were further selected to evaluate their neuroprotective effect on AD in vivo . Results showed that ergosterol and ganoderic acid DM could significantly alleviate Aβ 42 -induced cognitive dysfunction and hippocampus neuron loss in vivo . Moreover, ergosterol and ganoderic acid DM could significantly inhibit Aβ 42 -induced neuron apoptosis and Nrf2-mediated neuron oxidative stress in vitro and in vivo .

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., (Copyright © 2014 the authors 0270-6474/14/3413535-14$15.00/0.)

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.

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.