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In recent years, much attention has been paid to the therapeutic effects of phytochemicals on osteoporosis. Other studies have shown that myricetin (MY) could promote osteogenic activity and inhibit osteoclastic effect, albeit little is known about effect of MY micellar system on osteoporosis. Therefore, we sought to discuss the therapeutic effect and mechanism of MY-loaded bone-targeting micelles on osteoporosis induced by ovariectomy (OVA) in rats. The AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles were prepared via ethanol injection method, while in vitro release study, bone targeting, pharmacokinetic studies, and the effect on proliferation of osteoblasts were investigated. Further, the therapeutic effect on osteoporosis was studied through ovariectomized rats. Compared with free MY, oral bioavailability of AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles in rats was increased by 3.54 times. The AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles exhibited bone targeting potential, and could significantly increase the activity of alkaline phosphatase and promote the proliferation of osteoblasts. Importantly, AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles mainly regulated bone metabolism by inhibiting bone resorption, thereby improving the symptoms of osteoporosis in OVA rats. The AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles substantially enhanced the oral bioavailability of MY and demonstrated good bone targeting capability, thereby suggesting its prospect as carrier for osteoporotic improvement in OVA rats.

Numerical studies were performed to investigate the mechanism and potential of several active rotors for reducing low-frequency in-plane thickness noise generated by rotating blades. A numerical method coupling the blade element theory, prescribed wake model and Fowcs Williams-Hawkings (FW-H) equation was established for rotor noise prediction. It is indicated that the excitation force on the blade tip can generate anti-noise that to partly cancel the in-plane thickness noise with an appropriate actuation law. Results from the phase, frequency and amplitude sweeps show that the excitation force direction and actuation law are the crucial factors affecting the noise reduction, which determine the noise reduction area in the elevation and azimuth directions, respectively. The active trailing-flap rotor can generate the in-plane excitation force, but because of large lift-drag ratio the anti-noise is mainly from the vertical lift, which is caused by flap deflection similar to a variable camber airfoil. For the harmonic control rotor and active twist rotor, the excitation force is also attributed to the vertical blade lift. The vertical force can reduce the noise near the rotor plane, it will also cause the noise increase in most other areas. Finally, two new active rotors were proposed to generate the in-plane chordwise and spanwise excitation force. With the modified actuation law, the noise in most areas around the rotor was reduced, which improved the acoustic characteristics of rotor significantly.

Magnesium (Mg) and its alloys have emerged as a favored candidate for bio-regenerative medical implants due to their superior biocompatibility, biodegradability and the elastic modulus close to that of human bone. Unfortunately, the rapid and uncontrollable degradation rate of Mg alloys in chloride-rich body microenvironments limits their clinical orthopedic applications. Recently, Calcium Phosphate (Ca-P) biomaterials, especially Hydroxyapatite (HA), have been broadly applied in the surface functional modification of metal-based biomaterials attributed to their excellent bioactivity and biocompatibility. Hydrothermal modification of Ca-P coatings on Mg alloys has been extensively exploited by researchers for its significant superiorities in controlling coating structure and improving interfacial bonding strength for better osseointegration and corrosion resistance. This work focuses on the up-to-the-minute advances in Ca-P coatings on the surface of Mg and its alloys via hydrothermal methods, including the strategies and mechanisms of hydrothermal modification. Herein, we are inclined to share some feasible and attractive hydrothermal surface modification strategies. From the perspectives of hydrothermal manufacturing technique innovation and coating structure optimization, we evaluate how to foster the corrosion resistance, coating bonding strength, osseointegration and antibacterial properties of Mg alloys with Ca-P coatings synthesized by hydrothermal method. The challenges and future perspectives on the follow-up exploration of Mg alloys for orthopedic applications are also elaborately proposed.

Phosphorus (P) and nitrogen (N) are both essential macronutrients for maintaining plant growth and development. In rice (Oryza sativa L.), OsPHR3 is one of the four paralogs of PHR1, which acts as a central regulator of phosphate (Pi) homeostasis, as well being involved in N homeostasis. However, the functions of OsPHR3 in N utilization under different Pi conditions have yet to be fully studied. In this study, we aimed to dissect the effect of OsPHR3-overexpression on N utilization under Pi deficient regimes. Biochemical, molecular and physiological assays were performed to determine the N-influx, translocation, and accumulation in OsPHR3-overexpressing rice lines, grown under Pi-sufficient and -deficient conditions, in both hydroponic and soil systems. Furthermore, important agronomic traits of these plants were also evaluated. The overexpression of OsPHR3 increased N uptake under Pi stress regimes. Increased N uptake also elevated total N concentrations in these plants by inducing N transporter genes expression. Furthermore, overexpression of OsPHR3 increased N use efficiency, 1000-grain weight and grain yield under different Pi conditions. We established new findings that OsPHR3-overexpression facilitates N utilization under Pi deficient conditions. This will help achieving higher yields by coordinating the utilization of N and P.

Amino acids are essential plant compounds serving as the building blocks of proteins, the predominant forms of nitrogen (N) distribution, and signaling molecules. Plant amino acids derive from root acquisition, nitrate reduction, and ammonium assimilation. Many amino acid transporters (AATs) mediating transfer processes of amino acids have been functionally characterized in Arabidopsis, whereas the function and regulation of the vast majority of AATs in rice (Oryza sativa L.) and other crops remain unknown. In this review, we summarize the current understanding of amino acids in the rhizosphere and in metabolism. We describe their function as signal molecules and in regulating plant architecture, flowering time, and defense against abiotic stress and pathogen attack. AATs not only function in root acquisition and translocation of amino acids from source to sink organs, regulating N uptake and use efficiency, but also as transporters of non-amino acid substrates or as amino acid sensors. Several AAT genes show natural variations in their promoter and coding regions that are associated with altered uptake rate of amino acids, grain N content, and tiller number. Development of an amino acid transfer model in plants will advance the manipulation of AATs for improving rice architecture, grain yield and quality, and N-use efficiency.

Visual blindness affects many millions globally and severely impacts quality of life. One approach to overcome visual blindness is the direct electrical microstimulation of brain circuits normally engaged in visual function. Attempts to do so with traditional brain-machine interfaces (BMI) in monkeys and humans have evoked percepts (phosphenes) described as crude featureless spots of light. Here, we propose to qualitatively enhance these percepts by recruiting submillimeter units of cortical representation (cortical columns) which encode rich visual features such as color, motion, shape, and faces. A three step roadmap is proposed, comprising: (1) the mapping of column-based networks (columnar connectomes), (2) connectome-guided studies of circuitry and perception, and (3) column-targeted design of optical BMIs. We predict this approach will increase the specificity and sophistication needed for realistic, vibrant visual perception.

Background: Phosphate (Pi), is the least accessible macronutrient in many natural and agricultural ecosystems and its low availability often limits plant growth and productivity. In Arabidopsis thaliana (Arabidopsis), Phosphate Deficiency Response2 (AtPDR2), interacts genetically with Low Phosphate Root1 (AtLPR1) in the endoplasmic reticulum (ER), play a key role in Pi deficiency-mediated inhibition of the primary root growth and remodeling of the root system architecture (RSA). However, the role of OsPDR2, the homolog of AtPDR2, either in roots response to Pi deficiency and/or in growth and development has not been elucidated as yet. Results: Therefore, we investigated the spatiotemporal effects and the availability of Pi on the relative expression levels of OsPDR2 by employing qRT-PCR. OsPDR2 showed variable levels of relative expression pattern in vegetative and/or reproductive tissues analyzed at different stages of growth and development (5-17 weeks). Transient expression analysis revealed its subcellular localization to the ER. Further, the reverse genetics approach was employed for determining the function of OsPDR2 by RNAi-mediated suppression. Three independently generated RNAi lines (Ri2, Ri9, and Ri18) were compared with the wild-type (WT) for various vegetative and reproductive traits. The study revealed significant inhibitory effects of RNAi-mediated suppression of OsPDR2 on the root and male reproductive traits, and yield. Moreover, 32P isotope labeling and split-root experiments under different Pi regime with RNAi lines and the WT revealed the role of OsPDR2 in the maintenance of Pi homeostasis. Conclusions: The results from this study revealed the key role of OsPDR2 in the growth and development of rice and maintenance of phosphate homeostasis.

To improve the long-term corrosion resistance of biodegradable AZ31 magnesium alloy, the micro-nano structural hydroxyapatite (HA) coating was fabricated on AZ31 substrate by hydrothermal treatment. The compact and high crystallinity HA coating prepared at 120 °C had excellent electrochemical properties. Moreover, the cell viability experiment revealed that the micro-nano structure coating was conducive to the viability and proliferation of MC3T3-E1 osteoblasts. The immersion experiment in simulated body fluid (SBF) solution showed that the micro-nano structural HA coatings could quickly induce the production of HA mineralization, and then the mineralization evolved into a compact mineralized layer on the surface of coated sample, which provided a long-term protection for the specimen. Even after 147 days of immersion, the coated samples remained the relatively complete macroscopic shape, the corrosion rates were lower than 0.500 mm/y and the pH values of the SBF solution maintained in the range of 7.10–7.80, suggesting when these coated AZ31 magnesium alloys were used as degradable biomaterial implants, they could provide a long-term mechanical support during the healing of damaged bones.

Organic fertilizer is commonly used to increase crop yields and improve soil quality. However, it is unclear whether crops adapt to organic fertilizer by regulating metabolic pathways that are involved in nutrient utilization. In this study, we focused on the organic phosphorus (P

Magnesium (Mg) and its alloys exhibit an excellent prospect for orthopedic clinical application due to their outstanding biodegradability and mechanical adaptability. However, the rapid corrosion rate/latent device-associated infections may lead to a failed internal fixation of Mg-based implants. Herein, a novel composite coating consisted of outer copper-doped zeolitic imidazolate frameworks-8 and inner hydroxyapatite (Cu@ZIF-8/HA) was in situ constructed on AZ31B Mg alloy via a two-step approach of hydrothermal treatment and seeded solvothermal method. The results verified that the electrochemical impedance of the obtained Cu

Willows (Salix spp.) are promising extractors of cadmium (Cd), with fast growth, high biomass production, and high Cd accumulation capacity. However, the molecular mechanisms underlying Cd uptake and detoxification are currently poorly understood. Analysis of the Cd uptake among 30 willow genotypes in hydroponic systems showed that the S. suchowensis and S. integra hybrids, Jw8-26 and Jw9-6, exhibited distinct Cd accumulation and resistance characteristics. Jw8-26 was a high Cd-accumulating and tolerant willow, while Jw9-6 was a low Cd-accumulating and relatively Cd-intolerant willow. Therefore, these two genotypes were ideal specimens for determining the molecular mechanisms of Cd uptake and detoxification. To identify relevant genes in Cd handling, the parent S. suchowensis was treated with Cd and RNA-seq analysis was performed. SsIRT, SsHMA, and SsGST, in addition to the transcription factors SsERF, SsMYB, and SsZAT were identified as being associated with Cd uptake and resistance. Because membrane-localised heavy metal transporters mediate Cd transfer to plant tissues, a total of 17 SsIRT and 12 SsHMA family members in S. suchowensis were identified. Subsequently, a thorough bioinformatics analysis of the SsIRT and SsHMA families was conducted, and their transcript levels were analysed in the roots of the two hybrids. The transcript levels of SsIRT9 in roots were positively correlated with the observed differences in Cd accumulation in Jw8-26 versus Jw9-6. Jw8-26 displayed higher SsIRT9 expression levels and higher Cd accumulation than Jw9-6; therefore, SsIRT9 may be involved in Cd uptake. Gene expression analysis also revealed that SsHMA1 was a candidate gene associated with Cd resistance. These results lay the foundation for understanding the molecular mechanism of Cd transfer and detoxification in willows, and provide guidance for the screening and breeding of high Cd-accumulating and tolerant willow genotypes via genetic engineering.

The development of corrosion resistance biological coatings on magnesium and its alloy that can be used for controlling the degradation rate and corresponding biological properties from the surface of implants could have a significant impact in the field of bone tissue regeneration. This work reported the fabrication of quickly deposited biphasic calcium phosphate (CaP) coatings on alkali (sodium hydroxide, NaOH) and acid (hydrofluoric, HF) pretreated magnesium alloy (AZ31) substrates using microwave assisted method. The results indicated that the pretreatment layers (formed on NaOH or HF pretreated AZ31 substrates) could protect substrates from etching of H+ during the deposition process of CaP coating. Meanwhile, different pretreatment layers have been shown to greatly influence the phase component, morphology, thickness and corrosion resistance of the resultant CaP coatings. The CaP coating based on the acid pretreatment layer was mainly composed of compact chrysanthemum-like F-doped hydroxyapatite (HA) with obvious c-axis growth orientation and exhibited excellent corrosion resistance in the simulated body fluid (SBF), which could provide more than 10 weeks of protection for magnesium alloy substrate.

This paper addresses the design of an improved line-of-sight (LOS) based adaptive trajectory tracking controller for an under-actuated AUV subjects to highly coupled nonlinearities, ocean currents-induced uncertainties, and input saturation. The influences of ocean currents on the AUV are expressed in a comprehensive way such that both the kinematic and dynamic models of AUV are established with ocean currents. Extended disturbance observers (EDO) are utilized to estimate the ocean currents-induced uncertainties as well as their time-derivatives. An improved LOS guidance law is designed by introducing an auxiliary variable to the conventional LOS, and utilizing extended disturbance observers to estimate the ocean current-induced disturbances in the kinematic model. EDO-based adaptive terminal sliding mode control method is employed for dynamic control to improve the tracking performance and converging rate. In addition, the influence of actuator saturation is weakened by anti-windup compensator. Rigorous theoretical analysis and extensive simulation studies demonstrate that the proposed approach has good tracking accuracy, stability, and anti-jamming ability, thus leading to satisfying trajectory tracking control.

A numerical method based on Reynolds Averaged Navier–Stokes (RANS) equations and moving overset mesh technique is developed to simulate the aerodynamics of Harrington rotor-2. A high-efficient trim model for hover is presented and coupled into the numerical method and the “delta trim arithmetic” is implemented to simplify the calculation of Jacobian matrix. Validation cases are computed, showing reasonably coincident with the available experimental data. Hover cases of different thrust coefficients with torque-balanced are conducted. Specially, zero-lift and one-rotor-stay cases are set for a better understanding of the interaction mechanism. Results indicate that the temporal thrusts of the coaxial rotor show a variation of gradually increasing and sharply decreasing. Different from the previous work, the fluctuation features are mainly explained by strong-weak “induction effect” and impulsive “overlap effect” caused by the interaction of wakes and bound vortexes of coaxial rotor. At a positive attack angle, the induction and overlap effects are more evident for the upper rotor because the induced flow is stronger above the blade than that below it. The first impulse of thrust caused by overlap effect takes place at about 3° azimuth after the alignment of the blades for present cases, as the upper and lower blades meet in a rotating way.

Nitrogen (N) is the most abundant mineral nutrient required by plants, and crop productivity depends heavily on N fertilization in many soils. Production and application of N fertilizers consume huge amounts of energy and substantially increase the costs of agricultural production. Excess N compounds released from agricultural systems are also detrimental to the environment. Thus, increasing plant N uptake efficiency is essential for the development of sustainable agriculture. Arbuscular mycorrhizal (AM) fungi are beneficial symbionts of most terrestrial plants that facilitate plant nutrient uptake and increase host resistance to diverse environmental stresses. AM association is an endosymbiotic process that relies on the differentiation of both host plant roots and AM fungi to create novel contact interfaces within the cells of plant roots. AM plants have two pathways for nutrient uptake: either direct uptake via the root hairs and root epidermis, or indirectly through AM fungal hyphae into root cortical cells. Over the last few years, great progress has been made in deciphering the molecular mechanisms underlying the AM-mediated modulation of nutrient uptake processes, and a growing number of fungal and plant genes responsible for the uptake of nutrients from soil or transfer across the fungi-root interface have been identified. Here, we mainly summarize the recent advances in N uptake, assimilation, and translocation in AM symbiosis, and also discuss how N interplays with C and P in modulating AM development, as well as the synergies between AM fungi and soil microbial communities in N uptake.

To introduce an innovative surgical technique, transvertebral bone graft and augmentation (TBGA), to and evaluate its clinical efficacy in treating osteoporotic vertebral body compression fractures (VCFs), with balloon kyphoplasty (BKP) as a control.A total of 81 patients with a single-level osteoporotic VCF underwent TBGA (n = 38) or BKP (n = 43) at our hospital between October 2012 and January 2015. The average duration of follow-up period was 27.9 months. The patients were evaluated with plain radiography, computed tomography, and magnetic resonance imaging preoperatively, immediately postoperatively, at 3- and 6-month follow-ups, and every 6 months thereafter. Clinical status was assessed using the Oswestry Disability Index (ODI) and a visual analog scale (VAS). In addition, parameters of anterior vertebral body height (AVBH), kyphosis angle (KA), adjacent segment degeneration (ASD), and complications were also compared between the 2 groups.Significant clinical improvements in ODI, VAS scores, AVBH, and KA were seen in both the TBGA and BKP groups after surgery (P0.05). However, the differences in improvements in ODI and VAS between the TBGA and BKP groups were not statistically significant (P0.05). The improvements in AVBH and KA were significantly better in the TBGA group (P0.05). Furthermore, the rates of ASD and complications were significantly lower in the TBGA group during the follow-up period (P0.05).TBGA is an effective and safe surgical technique that appears to be a promising alternative to BKP for the surgical treatment of osteoporotic VCFs.

Plant growth and reproduction are both energy-requiring processes; the necessary energy is supplied by the products of photosynthesis. Both the vegetative growth and reproductive success of rice are compromised by the absence of a functional copy of the gene OsHAK1. Here, a comparison between wild type rice and OsHAK1 knockout mutants not only confirmed the known detrimental effect of the absence of OsHAK1 on root growth, pollen viability and fertility, but also showed that sucrose phosphate synthase activity was lowered, and the sucrose content of the leaves was markedly increased, due to a partial block on the up-loading of sucrose into the phloem. The impaired allocation of sugar to the roots and spikelets caused by the knocking out of OsHAK1 was accompanied by a down-regulation in the leaf sheaths and panicle axes of genes encoding sucrose transporters (SUT genes), which are active in the phloem, as well as in the roots and spikelets of those encoding monosaccharide transporters (MST genes), which transport hexose sugars across the plant plasma membrane. The activity of sucrose synthase, acid invertase and neutral invertase in the roots of mutant plants assayed at the tillering stage, and in their spikelets, assayed during grain-filling, was significantly lower than in the equivalent organs of wild type plants. As a result, the supply of total soluble sugar, glucose and fructose to sink organs was reduced, consistent with the effect of the mutation on root growth and panicle fertility. Compared to wild type plants, the mutants accumulated less potassium (K) throughout the plant. The conclusion was that the failure to fully supply the demand of the mutant's sink organs for assimilate was responsible for its compromised phenotype, and that the deficiency in K uptake induced by the loss of OsHAK1 functionality was responsible for the disruption of sugar metabolism.

This retrospective cohort study was performed to investigate clinical efficacy of TBGA compared with pedicle screw fixation (PSF).A total of 86 eligible patients with single-level simple thoracolumbar compression fracture (TLCF) received TBGA (n = 41) or PSF (n = 45) from January 2013 to July 2015. The patients were evaluated using plain radiography, computed tomography, and magnetic resonance imaging preoperatively. The radiologic examinations were performed at each time point postoperatively. Clinical status was assessed using the Oswestry Disability Index (ODI) and visual analog scale (VAS) scores. In addition, anterior vertebral body height (AVBH), kyphosis angle (KA), radiologic adjacent segment pathology (RASP), and complication rates were also compared between the 2 groups. The average follow-up period of patients was 26.1 months.Significant clinical improvements in ODI, VAS, AVBH, and KA were achieved in both TBGA and PSF groups after surgery, respectively (P0.05). There was no statistical difference in improvements of ODI and VAS between the TBGA and PSF groups (P0.05). Similarly, improvements of AVBH and KA showed no statistical difference between the 2 groups (P0.05). In addition, the rates of RASP and complications in PSF group were significantly higher than the TBGA group during the follow-up period (P 0.05).TBGA can achieve satisfactory clinical effects in treatment of simple TLCF. TBGA involves shorter operative time, less blood loss, lower RASP, and lower complication rates and could be more suitable for the surgical treatment of simple TLCF.

A high-resolution simulation tool for rotorcraft aerodynamics is developed by coupling CFD with a Vorticity Transport Model (VTM). An Eulerian-based CFD module is used to model the blade near body flowfield, and a Lagrangian-based VTM module is employed for vortex tracking in the far wake. The coupling procedure is implemented by transmitting vortex sources to the VTM module and feeding boundary conditions back to the CFD module. The presented CFD/VTM hybrid solver is firstly validated by hover cases of three different rotor configurations. Simulation results, including the blade surface pressure distribution, rotor downwash, and hover figure of merit, exhibit favorable correlations with available experimental data. Then, a rotor operated in vertical descending flight with a fixed collective pitch is investigated. It is shown that the CFD/VTM coupling method is suitable for rotor wake simulation. Wake instabilities (far wake breakdown in hover and toroidal wake pattern in the vortex ring state) are successfully demonstrated with a moderate computational cost. Keywords: Descending flight, Hybrid method, Rotorcraft, Vortex ring state, Vorticity transport model

Strigolactones (SLs) are involved in the nutrient-dependent control of plant root and shoot architecture. The total sufficient uptake of nitrogen (N), and also its appropriate distribution, is essential for the normal growth and development of plants; however, the effect of SLs on N translocation in plants remains unknown. Here, the SL-signaling mutant dwarf 3 (d3), the biosynthesis mutant dwarf 10 (d10), and wild-type (WT) rice (Oryza sativa ssp. Japonica cv. Nipponbare) were used to investigate the relationship between N nutrition and the regulatory role of SLs. Relative to WT, the d10 mutant had a higher N concentration in older leaves but a lower N concentration in younger leaves, while the d3 mutant showed a considerably lower N concentration, especially in its younger leaves under normal N levels. By contrast, both d3 and d10 mutants contained higher N in their leaves under N-deficient conditions. The 15N uptake and distribution analysis revealed that the significantly different N concentrations among the d3, d10, and WT plants only occurred in their leaves, not in their roots. Moreover, when provided with an external supply of GR24, the synthetic SLs altered the leaf N distribution of the d10 mutant but not those of the d3 mutant and WT. Together, these results suggested that the effect of SLs on plant growth and development may be linked to N translocation to different shoot tissues.

Biomimicry strategies, inspired by nature, are being widely used in the design of advanced biomaterials. Learning from the topographic landscape of natural bone resorption surface, which consists of micron/submicron-scale resorption lacunae and nano-scale sharp-tipped collagen fibrils, herein, a biomimetic fluoridated hydroxyapatite (FHA) coating composed of bilayer arrays of nanoneedles with micron/nano-topography was constructed on magnesium alloy surface via a microwave aqueous approach. The FHA coating possesses micron/submicron-scale roughness so as to mimic resorption lacunae. In parallel, the nanoneedles exhibit similar size and shape to collagen fibrils, especially their sharp tips. The surface topography, growth mechanism, osteogenic differentiation capacity and protection performance of this FHA coating were investigated. In vitro biological test showed that FHA coating significantly enhanced osteogenic differentiation capacity comprared with hydroxyapatite (HA) coating. Moreover, simulated body fluid immersion test demonstrated that FHA coating combined with formed HA mineralized layer together offered favorable long-term protection for magnesium alloy. This work may provide a new avenue of biomimetic surface topography design for orthopaedic implants with superior osteogenic differentiation capacity and corrosion resistance for long-term osseointegration of implants and fast bone regeneration.

Drought impedes the acquisition of potassium (K) by restricting root growth, in turn causing a reduction in the plant's K nutritional status, thereby further depressing its tolerance of the stress. The product of RAA1 (Root Architecture Associated 1) is involved in the auxin-mediated development of the rice root system. Here, the introduction of a transgene comprising RAA1 driven by the promoter of HAK1, a gene which encodes a drought-enhanced K transporter, was shown to exert a positive effect on the size of the root system and the number of adventitious roots formed. Transgenic seedlings demonstrated a higher level of tolerance to moisture stress than wild type (WT) ones, accumulated more K, proline and abscisic acid and suffered a lower level of lipid peroxidation. The genes AKT1, HAK1 and HAK5 were all up-regulated in the roots of transgenic drought-stressed hydroponics-grown seedlings, as were several known stress-responsive genes in the leaves of soil-grown, moisture-stressed transgenic plants. Under moisture deficient conditions, the transgenic plants developed more effective tillers than did WT plants, showed an enhanced level of spikelet fertility and produced larger grains. While under moisture sufficient conditions there was no significant difference in the grain yield of the transgenic and WT lines, under water limiting conditions, the transgenics recorded a 20–40% grain yield advantage over the WT. The implication was that the promotion of root growth and development achieved by enhancing the expression of RAA1 in the root could represent a viable approach for enhancing the productivity of cereal crops exposed to moisture stress.

A robust unsteady rotor flowfield solver CLORNS code is established to predict the complex unsteady aerodynamic characteristics of rotor flowfield. In order to handle the difficult problem about grid generation around rotor with complex aerodynamic shape in this CFD code, a parameterized grid generated method is established, and the moving-embedded grids are constructed by several proposed universal methods. In this work, the unsteady Reynolds-Averaged Navier-Stokes (RANS) equations with Spalart-Allmaras are selected as the governing equations to predict the unsteady flowfield of helicopter rotor. The discretization of convective fluxes is accomplished by employing the second-order central difference scheme, third-order MUSCL-Roe scheme, and fifth-order WENO-Roe scheme. Aimed at simulating the unsteady aerodynamic characteristics of helicopter rotor, the dual-time scheme with implicit LU-SGS scheme is employed to accomplish the temporal discretization. In order to improve the computational efficiency of hole-cells and donor elements searching of the moving-embedded grid technology, the “disturbance diffraction method” and “minimum distance scheme of donor elements method” are established in this work. To improve the computational efficiency, Message Passing Interface (MPI) parallel method based on subdivision of grid, local preconditioning method and Full Approximation Storage (FAS) multi-grid method are combined in this code. By comparison of the numerical results simulated by CLORNS code with test data, it is illustrated that the present code could simulate the aerodynamic loads and aerodynamic noise characteristics of helicopter rotor accurately. Keywords: Aerodynamic characteristics, Helicopter rotor, Moving-embedded grid, Navier-Stokes equations, Upwind schemes

Despite the economic and evolutionary importance of aquatic host-infecting microsporidian species, at present, limited information has been provided about the microsporidia–host interactions. This study focused on Hepatospora eriocheir, an emerging microsporidian pathogen for the Chinese mitten crab Eriocheir sinensis. Hypertrophy of hepatopancreas cells was a common feature of H. eriocheir infection. More importantly, mitochondria of the hepatopancreas were drawn around the H. eriocheir, most likely to aid the uptake of ATP directly from the host. To better understand the crab anti-microsporidian response, de novo transcriptome sequencing of the hepatopancreas tissue was furtherly proceeded. A total of 47.84 M and 57.21 M clean reads were generated from the hepatopancreas of H. eriocheir infected and control groups respectively. Based on homology searches, functional annotation with 6 databases (Nr, Swiss-Prot, KEGG, KOGs, Pfam and GO) for 88,168 unigenes was performed. 2619 genes were identified as differently up-regulated and 2541 genes as differently down-regulated. Prominent functional categories enriched with differentially expressed genes (DEGs) were “ATP binding”, “mitochondrion and extracellular region”, “oxygen transporter activity”, “oxidoreductase activity”, “alanine, aspartate and glutamate metabolism”, “carbohydrate metabolic process”, “starch and sucrose metabolism” and “fatty acid biosynthesis”. These results confirmed a parasite external energy supply and an integrated metabolic stress. In addition, simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs) were also identified from the gene library. Taken together, these findings allow us to better understand the underlying mechanisms regulating interactions between H. eriocheir and the crab E. sinensis.

The effects of blade surface jet blowing on the reduction of rotor blade-vortex interaction (BVI) noise are investigated using the compressible Reynolds-averaged Navier-Stokes equations and the Ffowcs Williams-Hawkings equations. A detailed analysis of the accuracy of the Weighted Essentially Non-Oscillatory (WENO) scheme and Monotone Upstream-Centered Scheme for Conservation Laws for simulating the flow field and predicting the BVI noise is performed using a two-bladed scaled AH-1 helicopter main rotor undergoing BVI as the baseline case. Additionally, a grid convergence study is conducted. The BVI noise is accurately predicted using the fifth-order WENO scheme and high-resolution grid system (the prediction errors of the peak sound pressure are less than 4%). Surface boundary conditions are introduced to model the effect of jet blowing on the blade surface on the flow control of the baseline case. Blade surface blowing is analyzed near the trailing edge and the leading edge near the rotor tip. The results show that blowing near the blade trailing edge is effective for BVI mitigation by altering the tip vortex strength and increasing the blade-vortex miss distance. The sound pressure level is reduced by 2.6 dB, and the peak amplitude is attenuated by more than 30%, with a 9.8% loss in rotor thrust. Therefore, blowing near the trailing edge may be considered a promising approach for active BVI noise control.

Magnesium and magnesium alloys as promising biodegradable implants gain increasing interest. To improve their corrosion resistance and cytocompatibility, hydroxyapatite (HA) coatings with double-layer structure were synthesized on magnesium alloy through a rapid microwave aqueous chemical route. The coating prepared with microwave heating time of 10 min consisted of cotton-like HA as the surface layer and strip-like HA as the bottom layer, and the coating thickness was ∼10.0 μm. The growth kinetic, electrochemical property, degradation, mineralization and cytocompatibility of HA coated and naked magnesium alloys were investigated. Potentiodynamic polarization test demonstrated that corrosion current density of HA coated magnesium alloy prepared with microwave heating time of 10 min was ∼100 times lower than that of the naked counterpart. Immersion test indicated that the strip-like HA layer with thickness of ∼7.7 μm and low solubility endowed magnesium alloy with initial-stage protection; the nano-scale cotton-like HA layer exhibited high HA mineralization capacity. The mineralized layer reached ∼12.7 μm in thickness after 24 days’ immersion, eventually integrated with the original HA bilayer coating, providing favorable long-term protection for magnesium alloy. Moreover, HA coated magnesium alloy prepared with microwave heating time of 10 min enhanced osteoblast proliferation than the naked counterpart. These attractive results indicated that this HA bilayer coating is a potential protective coating on biodegradable magnesium and magnesium alloys for orthopedic application.

Strontium has been suggested to have beneficial effects on bone remolding when incorporated at a suitable dose in apatite. In this work, strontium doped hydroxyapatite coating was prepared on magnesium (Mg) alloy substrates via microwave assisted deposition method for the purpose of improving the corrosion resistance and bioactivity of the substrates. A homogeneous and crack-free strontium doped hydroxyapatite (SrHA) coating with a special dual-layer structure was successfully fabricated on Mg alloy substrates in a short time of 10 min under microwave irradiation. Immersion tests in simulated body fluid (SBF) revealed that SrHA coatings could provide protection for Mg alloys in the initial stage and simultaneously induce new apatite precipitation to form a dense layer on the coating surface, suggesting that the SrHA coatings could accelerate the apatite precipitation and thus improve the bioactivity of Mg alloy substrates. The long-term immersion and electrochemical tests revealed that the deposited apatite layer could markedly improve the corrosion resistance of the coated samples over the immersion period of 32 days.

To improve the bioactivity of titanium and its alloys, dense and uniform apatite coatings were prepared on Ti6Al4V titanium substrates using microwave assisted aqueous chemical method. The influence of the pretreatment to the titanium substrates and the Ca/P molar ratio of the microwave solution on the coating deposition and morphology, as well as the bioactivity of the coated samples were studied. Results showed that during the microwave process, alkali treatment followed by heat treatment to the titanium substrates would promote the rapid deposition of hydroxyapatite to form coating. And the morphologies of the apatite coatings could be adjusted by the Ca/P molar ratio of the microwave solution. After immersion test in simulated body fluid (SBF), the coated titanium alloy exhibits a good bioactivity by inducing the formation of apatite depositions.

High nitrogen (N) fertilization for maximizing crop yield commonly leads to postponed flowering time (heading date in rice) and ripening, thus affecting resources use efficiency and followed planting time. We found that N-mediated heading date-1 (Nhd1) can directly activate florigen gene OsHd3a in rice. Inactivation of either Nhd1 or OsHd3a results in delay and insensitivity to N supply of flowering time. Knockout of Nhd1 increases N uptake and utilization efficiency at low-to-moderate N level under both short- and long-day field conditions. Increasing glutamine, the product of N assimilation, can upregulate expression of Nhd1, which in turn downregulates OsFd-GOGAT expression and OsFd-GOGAT activity, displaying a Nhd1-controlled negative feedback regulatory pathway of N assimilation. Moreover, N fertilization effect on rice flowering time shows genetically controlled diversity, and single-nucleotide polymorphism in Nhd1 promoter may relate to different responses of flowering time to N application. Nhd1 thus balances flowering time and N use efficiency in addition to photoperiod in rice.

The work-hardening characteristic of nickel-based GH4141 superalloy was investigated using uniaxial compression tests with different cold deformations. Prior to compression, the solution treatment was optimized using the dissolving temperature of precipitations, the mean size of grains, and the microhardness of the samples. The typical true strain-stress curve included elastic deformation (e ≤ 0.03), elastoplastic transition (0.03 ≤ e ≤ 0.05), and plastic deformation (e ≥ 0.05) stages. The true strain-stress relationship was formulated on the basis of Tian-Zhang model. During the plastic deformation stage, the true stress gradually increased due to the increase in dislocation slip resistance caused by the formation of dislocation tangles and different boundaries. The hardening rate gradually decreased because of the tardy dynamic recovery, and the decreasing dislocation density increment caused by the formation of grain boundaries.

Rice (Oryza sativa) grown in paddy fields is an ammonium (NH4+)-preferring crop; however, its AMT-type NH4+ transporters that mediate root N acquisition have not been well characterized yet. In this study, we analyzed the expression pattern and physiological function of the OsAMT1.1 gene of the AMT1 subfamily in rice. OsAMT1.1 is located in the plasma membrane and is mainly expressed in the root epidermis, stele and mesophyll cells. Disruption of the OsAMT1.1 gene decreased the uptake of NH4+, and the growth of roots and shoots under both low NH4+ and high NH4+ conditions. OsAMT1.1 contributed to the short-term (5 min) 15NH4+ influx rate by approximately one-quarter, irrespective of the NH4+ concentration. Knockout of OsAMT1.1 significantly decreased the total N transport from roots to shoots under low NH4+ conditions. Moreover, compared with the wild type, the osamt1.1 mutant showed an increase in the potassium (K) absorption rate under high NH4+ conditions and a decrease under low NH4+ conditions. The mutants contained a significantly high concentration of K in both the roots and shoots at a limited K (0.1 mmol/L) supply when NH4+ was replete. Taken together, the results indicated that OsAMT1.1 significantly contributes to the NH4+ uptake under both low and high NH4+ conditions and plays an important role in N–K homeostasis in rice.

In the present study, our bioinformatics analysis first reveals the existence of a conserved guanine-rich sequence within the Zaire ebolavirus L gene. Using various methods, we show that this sequence tends to fold into G-quadruplex RNA. TMPyP4 treatment evidently inhibits L gene expression at the RNA level. Moreover, the mini-replicon assay demonstrates that TMPyP4 effectively inhibits the artificial Zaire ebolavirus mini-genome and is a more potent inhibitor than ribavirin. Although TMPyP4 treatment reduced the replication of the mutant mini-genome when G-quadruplex formation was abolished in the L gene, its inhibitory effect was significantly alleviated compared with wild-type. Our findings thus provide the first evidence that G-quadruplex RNA is present in a negative-sense RNA virus. Finally, G-quadruplex RNA stabilization may represent a new therapeutic strategy against Ebola virus disease.

To improve the corrosion resistance of AZ31 magnesium alloy, a crack-free hydroxyapatite/phytic acid (HA/PA) hybrid coating was synthesized on AZ31 substrate via a chemical conversion deposition to form precursor coating, and followed by a hydrothermal treatment in the saturated CaO solution. During the hydrothermal treatment, the phosphate and calcium ions diffused to the interface of the precursor coating/solution to form amorphous CaP compound and subsequently crystallized into HA particles that repaired the defects in the precursor coating and exhibited a high bonding strength of 24.3 ± 1.7 MPa between the hybrid coating and the magnesium alloy substrate. Electrochemical measurements in simulated body fluid (SBF) revealed that the HA/PA hybrid coating could effectively provide protection for magnesium (Mg) alloy on account of the stable barrier properties.

Hydrogen production via cyclohexane dehydrogenation catalyzed by a Raney-Ni catalyst under multiphase reaction conditions was investigated in this study. The uniform design (UD) method was employed to optimize the performance of the dehydrogenation reaction system of cyclohexane under “wet–dry” multiphase reaction conditions and to evaluate the effects of the process parameters on several response functions, such as the total amount of hydrogen produced in 2 h, the dehydrogenation conversion of cyclohexane and the relative activity of the catalyst. The results indicated that the data were well fitted by the regressed second-order polynomial models. Optimum reaction conditions for each response were obtained, under which the total amount of hydrogen produced in 2 h reached 9280 ml, the hydrogen produced through the conversion of cyclohexane was 18.63 and the relative activity of the catalyst maintained 0.91. In addition, the optimum reaction conditions for multi-response optimization were obtained, under which all three responses were expected to exhibit a relatively good performance. Confirmation experiments demonstrated that the UD method is a powerful and useful approach for optimizing the system of cyclohexane dehydrogenation under multiphase reaction conditions and is expected to provide valuable information for both efficient and economical hydrogen production.

This paper focuses on motion controller design for x-rudder underwater vehicles with four independent stern rudders where the conventional ganging method for maneuvering is not applicable. To realize the cooperation of the stern rudders, motion controller of an x-rudder underwater vehicle is divided into two parts, a dynamics controller and a control allocator. The controller design is conducted under both scenarios that model parameters are known and unknown. For known models, the desired maneuvering moments are generated by model based sliding mode control method. For unknown models, non-model based iterative sliding mode control method is utilized to calculate virtual steering rudder commands. The control allocator of both methods are based on sequential quadratic programming to solve the mixed minimum problem, with varied evaluation criterions and constraints. By conducting numerical simulations under various conditions, the functionality of the two proposed control methods are verified, and comparison in terms of accuracy, energy saving, and computation consumption are also discussed in detail.

The issue of single helicopter shipboard landing has been widely studied. This paper focuses on the helicopters/ship dynamic interaction for simultaneous landing of two helicopters. A numerical method combining the Detached Eddy Simulation, momentum source model and flight mechanics model via a one-way coupling strategy is developed. With this method, the coupling ship/helicopter flow-field and its effect on unsteady loading and handling behaviors of downwind shipborne helicopter at different conditions are investigated. The results show that in the headwind condition, the super vortex, formed by the upwind rotor wake merging into the deck-edge and superstructure vortex, is a principal factor affecting the downwind helicopter landing operation. Influenced by super vortex, high level of turbulence intensity is evident in the coupling ship airwake, giving rise to a sharp increase in unsteady loading levels and perturbations in control inputs and attitudes, compared with the baseline case (without upwind rotor), and pedal control margin is reduced accordingly. While increasing the translation height can effectively weaken the effect of super vortex, thereby reducing unsteady loading levels and alleviating control margin limits. When wind-over-deck (WOD) angle increases, despite no super vortex formed, the inclined upwind rotor wake interacting with the shear layer in ship airwake results in a higher level of turbulence intensity in the area over the deck. Perturbations in unsteady loading levels, controls and attitudes are more pronounced and complicated than the headwind case, causing great pilot workload.

In this research, a one-way coupling numerical method for the ship-helicopter dynamic interface was developed in combination with a Detached Eddy Simulation and a helicopter flight mechanics model. Using the method, the effects of the active and passive flow control (i.e., active jet and notch) on ship-helicopter dynamic interface was investigated, especially the control margin and unsteady aerodynamic loading characteristics of a shipborne helicopter. The results showed that although the notch modification could reduce the unsteady aerodynamic loading level, it also increased the lateral velocity component of the ship airwake, which led to the increase of the roll angle of the helicopter and the decrease of the pedal margin. In comparison, the active jet control could reduce pilot workload while had little adverse effect on control margin. The parametric studies indicated that the jet with proper strength and frequency can reduce the lateral turbulence intensity and turbulent kinetic energy levels, and alleviates the pilot workload, but if the strength and frequency is high, the small-scale vortex generated by the jet itself will make the ship airwake disordered, which has a negative effect on the control ability of the active jet to decrease the unsteady level of ship airwake. In addition, the control ability of the unsteady jet was not good as that of steady jet when the jet momentum coefficient was constant.

Plant HAK/KUP/KT family members function as plasma membrane (PM) H+/K+ symporters and may modulate chemiosmotically-driven polar auxin transport (PAT). Here, we show that inactivation of OsHAK5, a rice K+ transporter gene, decreased rootward and shootward PAT, tiller number, and the length of both lateral roots and root hairs, while OsHAK5 overexpression increased PAT, tiller number, and root hair length, irrespective of the K+ supply. Inhibitors of ATP-binding-cassette type-B transporters, NPA and BUM, abolished the OsHAK5-overexpression effect on PAT. The mechanistic basis of these changes included the OsHAK5-mediated decrease of transmembrane potential (depolarization), increase of extracellular pH, and increase of PM-ATPase activity. These findings highlight the dual roles of OsHAK5 in altering cellular chemiosmotic gradients (generated continuously by PM H+-ATPase) and regulating ATP-dependent auxin transport. Both functions may underlie the prominent effect of OsHAK5 on rice architecture, which may be exploited in the future to increase crop yield via genetic manipulations., The potassium transporter OsHAK5 in rice acts as a convergence point between the developmental pathways of tillering, lateral root and root-hair growth, and the auxin transport pathway. This study reveals dual roles of OsHAK5 in altering cellular chemiosmotic gradients (generated continuously by plasma membrane H+-ATPase) and regulating ATP-dependent auxin transport.

Gemcitabine (Gem), an analogue of deoxycytidine, has potent antitumor activities against various solid tumors and is an excellent radiosensitizer as well. However, Gem has a very short half-life, making it difficult to achieve the long-term synergies between chemotherapy and radiotherapy. Herein, we developed a long-acting Gem delivery system using a palmityl modified Gem derivative (GemC16) as the drug and an injectable and thermosensitive hydrogel as the vehicle, and then combined with multiple radiation therapy for the synergistic treatment of tumors. The thermosensitive hydrogel that exhibited a temperature-responsive sol–gel transition was composed of two poly(D,L-lactic acid-co-glycolic acid)-b-poly(ethylene glycol)-b-poly(D,L-lactic acid-co-glycolic acid) (PLGA-PEG-PLGA) triblock copolymers with different PLGA/PEG ratios. Such a physical hydrogel formed an internal structure of percolated micelle network, in which the polymeric micelles played a reservoir role in effectively solubilizing lipophilic GemC16 in water. In vitro tests manifested that the entrapped GemC16 was, in the form of micelles and micellar aggregates, released out of the hydrogel depot in a sustained pattern for over one month. In vitro cellular assays demonstrated that GemC16 mediated by the polymeric micelles was rapidly internalized to tumor cells via endocytosis. After a single peritumoral administration of the hydrogel system combined with local multiple X ray exposures, the sustained release of GemC16 exerted a long-acting chemotherapy effect and afforded a durable radiosensitization, thereby synergistically enhancing chemoradiotherapy efficacy, inhibiting metastasis and ameliorating complications.

In order to improve the biological activity and antibacterial activity of magnesium alloy, the single zinc oxide (ZnO) coating was prepared on magnesium alloys using microwave aqueous synthesis method and followed heat treatment. Then, the coated magnesium alloys were irradiated with ultraviolet (UV) light for different time and subsequently immersed in simulated body fluids (SBF). The influences of UV-irradiated time on the morphology, composition, in vitro biological activity and antibacterial activity were investigated. The results indicated that the ability of the apatite formation on the ZnO coated magnesium alloys surface was significantly enhanced as UV irradiation time prolonged, and the bone-like apatite was formed after UV irradiation for 24 h and then immersing into SBF for 2 weeks, the newly formed apatite was dense and integrate, implying that UV irradiation could activate ZnO coating to improve the biological activity. Moreover, after immersing in SBF for 2 weeks, the antibacterial experiment results demonstrated that ZnO coated magnesium alloys with UV irradiation time of 24 h exhibited more effective antibacterial activity than those of naked magnesium alloys and ZnO coated magnesium alloys which were not irradiated by ultraviolet (UV) light. This work afforded a surface strategy for designing magnesium alloy implant with desirable osseointegration ability and antibacterial property simultaneously for orthopedic and dental applications.

The rate constant for the CF3O + NO reaction has been studied with the variable reaction coordinate transition-state theory and multichannel RRKM calculation based on the potential energy surface obtained by the G3B3//UB3LYP/6-311+G(3df) level of theory. The total rate constant was found to exhibit weak negative temperature dependence, in line with most experimental results. The formation of FNO + CF2O is dominant at ambient temperature. The branching ratio of FNO + CF2O accounts for 0.922–0.618 at T = 150–3000 K peaking around 400 K. When temperature rises, the FON + CF2O channel becomes more and more appreciable, the branching ratio of FON + CF2O accounts for 0.001–0.382 at T = 150–3000 K increasing with temperature. At room temperature, the total rate constant is almost independent of the pressure, in agreement with previous experimental result.