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A full rollout of COVID-19 vaccination offers the most promising prospect of bringing the pandemic to an end. This study aimed to compare the coverage, safety, and confidence of COVID-19 vaccination between patients with Parkinson's disease (PD) and healthy individuals so as to give suggestions for future immunization programs. A web-based, nationwide, multicenter survey was carried out in China from 2021 to 2022. The age and sex-standardized vaccination rate was calculated. Multivariate stepwise logistic regression models were used to estimate the influencing factors of vaccination status. We also investigated vaccination safety, willingness, confidence, and reasons for hesitancy with some ad hoc questions. A total of 962 PD patients and 1208 healthy individuals participated in this survey with a vaccination rate of 71.1% vs 94.4% respectively. PD patients living in first-tier cities, with comorbidities, experiencing unstable PD with a longer course and levodopa use were less likely to get vaccinated, while healthy individuals living in first-tier cities and feeling physically poor exhibited a lower vaccination rate. For PD patients, concern about the adverse impact on existing illness and disagreement from doctors were the most common reasons for vaccination hesitancy. Whereas, no evidence was present that they experienced any local or systematic adverse events more frequently or seriously than healthy individuals, or their state of PD and comorbidities was seriously exacerbated after vaccination. A prominent transition from a little concerned to unconcerned about the security and efficacy of vaccines was evident among both two populations from pre-vaccination to post-vaccination. The COVID-19 vaccination rate was remarkably lower in PD patients than healthy individuals in China. The approved vaccines have shown an acceptable safety profile. Our findings would offer a reference to guide future clinical decision-making of COVID-19 vaccination and improve the immunization management of PD patients. [ABSTRACT FROM AUTHOR]

Inhomogeneous microstructures in the thickness direction and stress corrosion cracking of 2050-T84 Al-Li alloy thick plate was investigated. The quarter layer of alloy thick plate exhibited the highest stress corrosion cracking sensitivity, which was related to AlCuMnFe IMPs, subgrains, orientation, T 1 phase and dislocation density. In the quarter layer, the obstruction of subgrains to deformation bands resulted in significant stress concentration. Cracks originated from corrosion pits caused by AlCuMnFe IMPs around subgrains. The dealloying corrosion of T 1 phase and the presence of Goss texture increased the brittleness of the alloy, further accelerating the stress corrosion cracking of the quarter layer. • Inhomogeneous microstructures of 2050-T84 alloy induce differences in SCC sensitivity. • Obstruction of subgrains to deformation bands result in stress concentration. • Cracks originate from corrosion pits caused by AlCuMnFe IMPs around subgrains. • Dealloying corrosion of T 1 phase increases the brittleness and SCC sensitivity of 2050-T84 alloy. [ABSTRACT FROM AUTHOR]

• The Bi 2 Te 3 nanoflakes was fabricated by liquid-phase exfoliation and characterized. • Applying the Bi 2 Te 3 SA, a dual-loss-modulated QML IOPO laser was realized, resulting in the generation of sub-nanosecond single mode-locking pulses. • The rate equations for IOPO driven by the QML laser with Bi 2 Te 3 SA were numerically solved. By utilizing the ultrasound-assisted liquid phase exfoliation process, Bi 2 Te 3 nanosheets are synthesized and deposited onto a quartz plate to form a saturable absorber (SA), in which nonlinear absorption characteristics around 1 μm are investigated with a home-made Q-switched laser. With the as-prepared Bi 2 Te 3 SA employed, a sub-nanosecond KTiOPO 4 (KTP) based intracavity optical parametric oscillator (IOPO) pumped by a dual-loss-modulated Q-switched and mode-locked (QML) laser is successfully realized. With a short duration of sub-nanosecond and a repetition rate of several kilohertz (kHz), the signal wave's single mode-locking pulse existed underneath a Q-switched envelope can be formed. At an incident pump power of 8.92 W and an acousto-optic modulator (AOM) repetition rate of 2 kHz, a signal wave's single mode-locking pulse underneath a Q-switching envelope with a measured minimum pulse duration of 520 ps is accomplished. It is the first demonstration of such Bi 2 Te 3 SA utilized in a solid-state QML IOPO laser, to the best of our knowledge. According to the experimental results, this provides an efficient and straightforward approach to acquire sub-nanosecond OPO signal wave pulses. Additionally, the relevant coupled rate equations are established, and the simulation results match the experimental results, revealing the potential of Bi 2 Te 3 as a nanomaterial for optoelectronic applications. [ABSTRACT FROM AUTHOR]

In recent years, the installed capacity of wind power has rapidly increased. And the wind power prediction is the foundation for ensuring large-scale wind power grid connection. The current short-term prediction methods of wind farm cluster (WFC) are difficult to sufficiently extract spatiotemporal features to achieve high-precision prediction. The article proposes a short-term power prediction method for WFC based on deep attention embedded graph clustering-TimesNet (DAEGC-TimesNet). Firstly, the directed power curves of WFC are proposed to analyze wind data. Then, a graph attention network is constructed based on geographic location and numerical weather prediction (NWP) information to guide clustering algorithms to achieve effective cluster partitioning. Finally, the input of model is constructed based on the feature information from various sub-clusters of WFC and the prediction result is obtained through the TimesNet. The method is applied to WFCs in Inner Mongolia, Jilin province and Yunnan province of China. The result shows that the RMSE reduces 0.0155 and the MAE reduces 0.0156 as well as the coefficient of determination and accuracy rate are highest comparing with comparative algorithms averagely based on above three WFCs. The simulation results are superior to the comparison algorithms, which makes greater contributions to ensure regional power supply. [Display omitted] • Propose a directed power curves of wind farm cluster. • Propose a new short-term power prediction method for wind farm cluster. • Propose a short-term prediction method based on multi-source spatiotemporal feature. • It provides new ideas for short-term wind power prediction for wind farm cluster. • Proposed power prediction idea reduces the RMSE and MAE 0.0155 and 0.0156 on average. [ABSTRACT FROM AUTHOR]

Climate change is increasing flooding in provinces of the south of the Yangtze River, posing challenges for promoting Styrax tonkinensis seedlings in these areas. To understand the physiological reasons for this species' intolerance to waterlogging, we observed biochemical parameters in one-year-old S. tonkinensis seedlings during two seasons. For 4 and 12 days in summer and winter experiments, respectively, we subjected seedlings to a pot-in-pot waterlogging treatment. Control groups were established at 0 h and 0 days. We examined indicators related to root vigor, reactive oxygen species (ROS), antioxidant enzymes, fermentative pathways, and more. The results displayed that decreased abscisic acid accumulation in roots inhibited water transport. Increased dehydrogenase and lactate dehydrogenase activity in roots promoted alcohol and lactate fermentation, causing toxic damage and reduced root vigor, impeding water absorption. In leaves, high ROS levels led to lipid peroxidation, exacerbating water loss from continuous transpiration. The high relative electric conductivity and low leaf relative water content indicated water loss, causing leaf wilting and shriveling. Conversely, winter seedlings, devoid of leaves, significantly reduced transpiration, and dormancy delayed root fermentation. With less ROS damage in roots, winter seedlings exhibited greater waterlogging tolerance. In summary, excessive water loss from leaves and inhibited vertical water transport contributed to low summer survival rates, while winter leafless dormancy and reduced ROS damage enhanced tolerance. Our findings provide insights for enhancing waterlogging resistance in S. tonkinensis amidst climate change challenges. • Reduced root vigor, decreased ABA content, active root fermentation hindered water absorption in roots. • ROS accumulation, lipid peroxidation, and transpiration led to leaf water loss. • Leaf water loss and water transport inhibition caused low S. tonkinensis survival. [ABSTRACT FROM AUTHOR]

• SAM enhances innate immunity by reducing the bacterial burden in the intestine. • SAM induces the expression of immune response genes, including irg-1 and T24B8.5. • SAM functions in germline to enhance innate immunity via an H3K4 methyltransferase complex to up-regulate the immune response genes. • SAM protects mice from P. aeruginosa PA14 infection by reducing the bacterial burden in lung. S-adenosylmethionine (SAM) was a methyl donor for modifying histones, which had crucial roles in lipid accumulation, tissue injury, and immune responses. SAM fluctuation might be linked to variations in histone methylation. However, the underlying molecular mechanisms of whether the SAM diet influenced the immune response via histone modification remained obscure. In this study, we utilized the Caenorhabditis elegans as a model to investigate the role of SAM diet in innate immunity. We found that 50 μM SAM increased resistance to Gram-negative pathogen Pseudomonas aeruginosa PA14 by reducing the bacterial burden in the intestine. Furthermore, through the genetic screening in C. elegans , we found that SAM functioned in germline to enhance innate immunity via an H3K4 methyltransferase complex to upregulate the immune response genes, including irg-1 and T24B8.5. Intriguingly, SAM also protected mice from P. aeruginosa PA14 infection by reducing the bacterial burden in lung. These findings provided insight into the mechanisms of molecular connections among SAM diet, histone modifications and innate immunity. [ABSTRACT FROM AUTHOR]

In order to suppress the interference of speckle noise on the quality of hologram an attention-wavelet residual denoising network based on multi-level wavelet convolutional neural network is proposed. Firstly, the phase-only hologram is input into the network, and the wavelet transform of the shrinkage subnet is used instead of pooling to reduce the size of the hologram and expand the receptive field. Secondly, the attention-residual module which embeds the convolutional block attention module(CBAM) into the residual block is added to each layer of the network. The CBAM is used to capture the speckle noise of the hologram more accurately, and to improve the fusion capability of network feature information through the residual block. Finally, the hologram after denoising is obtained by up-sampling in the extended subnet by inverse wavelet transform. Simulation experiments show that the improved network effectively removes speckle noise while obtaining high quality holograms. • Denoising of phase-only holograms by attentional wavelet residual networks. • Discrete wavelet transform embedded in convolutional neural networks. • Speckle interference fringing maps simulate phase-only holograms. • Convolutional Block Attention Module and Residual Block to improve noise extraction. [ABSTRACT FROM AUTHOR]

Kiwifruit is a climacteric fruit that is prone to ripening and softening. Understanding molecular regulatory mechanism of kiwifruit softening, is helpful to ensure long-term storage of fruit. In the study, two NAC TFs and two XTH genes were isolated from kiwifruit. Phylogenetic tree showed that both AcNAC1 and AcNAC2 belonged to NAP subfamily, AcXTH1 belong to I subfamily, and AcXTH2 belong to III subfamily. Bioinformatics analysis predicted that AcNAC1 and AcNAC2 possessed similar three-dimensional structural, and belonged to hydrophilic proteins. AcXTH1 and AcXTH2 were hydrophilic proteins and contained signal peptides. AcXTH1 had a transmembrane structure, but AcXTH2 did not. qRT-PCR results showed that AcNAC1 , AcNAC2 , Ac XTH1 and AcXTH2 were increased during kiwifruit ripening. Correlation analysis showed that kiwifruit softening was closely related to endotransglucosylase/hydrolase genes and NAC TFs, as well as there was also a close relationship between AcXTHs and AcNACs. Moreover, both AcNAC1 and AcNAC2 were transcriptional activators located in nucleus, which bound to and activated the promoters of AcXTH1 and AcXTH2. In shortly, we proved that the roles of NAC TFs in mediating fruit softening during kiwifruit ripening. Altogether, our results clarified that AcNAC1 and AcNAC2 were transcriptional activators, and took part in kiwifruit ripening and softening through activating endotransglucosylase/hydrolase genes, providing a new insight of fruit softening network in kiwifruit ripening. • AcNAC1 , AcNAC2 , AcXTH1 and AcXTH2 were raised during kiwifruit repening. • Both AcNAC1 and AcNAC2 were transcriptional activators located in nucleus. • AcNAC1 and AcNAC2 could bind to and activate AcXTH1 and AcXTH2 promoters. [ABSTRACT FROM AUTHOR]

[Display omitted] • The catalysts contain multi-active sites. • The micro twinning structure promotes catalytic activity towards different reactions. • The synergic effect exists and leads to the deviation from the Scaling Effect. The twinning structure could lead to unexpected effects on electrocatalytic performance; however, research on relevant mechanisms is still rare and there is still a lack of an effective and convenient strategy to introduce twinning structures into nanoparticles. In this work, inspired by the in-situ fcc-hcp phase transition in metals and benefiting from the features of Prussian blue analogues (PBAs), N-doped carbon cages-coated CoNi nanoparticles, which contain multi-active sites including alloyed nanoparticles, micro twinning structures and single atom sites could be effectively fabricated by pyrolyzing of CoNi-based PBAs. The catalyst exhibits an obvious enhancement in oxygen evolution/reduction reaction and hydrogen evolution reaction under alkaline conditions. Theoretical calculations verify that the micro-twinning structures originating from the fcc-hcp phase transition promote electrocatalytic activities significantly due to the optimized adsorption energy towards different intermediates. Moreover, the synergic effect between the multi-active sites may further optimize the electronic structures and lead to the deviation from the Scaling Effect. The water-splitting device and Zinc-Air battery are also assembled based on this micro- twinning electrocatalyst, which yields a maximum power density of 95 mW cm−2 and a low voltage of 1.76 V to reach 10 mA cm−2 current density, respectively. In all, this work contributes a simple and universal strategy to introduce both the multi-active sites and the twinning structure into transition metal-based catalysts, which improves the multi-catalytic activity towards different reactions significantly. [ABSTRACT FROM AUTHOR]

Hovering technology, as one of the core technologies in on-orbit service (OOS) missions, enables the relative position between an active spacecraft and chief spacecraft to be maintained within a given range, and it has received widespread attention in recent years. In this study, for an elliptical reference orbit, we proposed a series of control strategies to maintain a teardrop hovering formation with a J 2 perturbation. First, we formulated a mathematical model of the teardrop hovering formation maintained by the impulse control and presented a rapid method based on a relative-position correction method. Based on the sensitivity matrix, a strategy for maintaining a hovering formation using constant-thrust control was obtained. Furthermore, based on the proposed fast iterative method, an improved strategy was developed to satisfy a magnitude constraint. Finally, we analyzed the influence of the reference orbital elements and formation parameters on the hovering formation using numerical simulations, which demonstrated the efficiency of the proposed method. This provides a reference for the preliminary design of hovering formations. • The constant-thrust strategies for maintaining teardrop formation are proposed. • The magnitude constraint of engine is considered in the constant-thrust strategy. • Compared with traditional way, the proposed constant-thrust strategies save fuel. • The influence of the parameters on total impulse for maintenance are analyzed. [ABSTRACT FROM AUTHOR]

BaHf 0.8 Ln 0.2 O 3-δ doped with rare earth elements with different ionic radii (Ln = Yb, Y, Dy and Gd) as candidate materials for solid oxide fuel cells and H 2 separation membrane have been prepared. Their phase composition, sinterability, chemical stability and conductivity were studied systematically. The rare earth elements are successfully incorporated into the main phase crystal lattice of barium hafnate to generate a single perovskite phase. The relative density of all samples sintered at 1600 °C reaches above 90%, and Y-doped BaHfO 3 has the highest relative density (94.7%) and the biggest grain size (about 1 μm) among all samples. The conductivities of the samples firstly increase and then decrease with the increase of the doped ion radius. Among all samples the conductivity of BaHf 0.8 Y 0.2 O 3-δ is the highest and reaches 6.02 × 10−3 S cm−1 in wet air at 700 °C, which is attributed to the good sinterability and suitable crystal structure (tolerance factor and free volume). All samples also show excellent chemical stability in the test atmospheres, including saturated H 2 O steam, pure H 2 and CO 2 , 200 ppm H 2 S/Ar and boiling water. The Pt/BaHf 0.8 Y 0.2 O 3-δ electrolyte/Pt single cell was fabricated with a 530 μm-thick disk and its electrochemical properties were tested. The peak power density reaches 10.21 mW cm−2 at 700 °C, which is comparable to similar fuel cells reported. These results suggest that BaHf 0.8 Y 0.2 O 3-δ is a promising electrolyte candidate for proton-conducting fuel cells. BaHf 0.8 Ln 0.2 O 3-δ (Ln = Yb, Y, Dy and Gd) proton conductors were prepared. Among all samples BaHf 0.8 Y 0.2 O 3-δ sintered at 1600 °C displays the highest relative density, the largest grain size, the highest conductivity and protonic content. [Display omitted] • BaHf 0.8 Ln 0.2 O 3-δ (Ln = Yb, Y, Dy and Gd) proton conductors were prepared. The samples display excellent chemical stability. • Among all samples, BaHf 0.8 Y 0.2 O 3-δ shows the highest conductivity of 6.02 × 10−3 S cm−1 in wet air at 700 °C. • The Pt/BaHf 0.8 Y 0.2 O 3-δ /Pt single cell displays a peak power density of 10.21 mW cm−2 at 700 °C. [ABSTRACT FROM AUTHOR]

Satellite formation plays an important role in space missions such as on-orbit services and distributed space facilities. In these missions, hovering in a bounded range is one of the core tasks, but hovering technologies for the chief satellite in an elliptical orbit have been rarely investigated. Given the boundary constraints of relative motion between the chief and deputy satellites, this paper proposes two models for the design and control of hovering formation near an elliptical reference orbit through impulse: (1) the revisiting hovering formation model, which forces the deputy satellite to revisit the same relative position and maintains the formation via impulses; (2) the sequential-impulse-control hovering formation model, which uses a sequence of impulses to ensure the deputy satellite flies within the given boundary. Unlike the revisiting hovering formation model, this model does not require a fixed revisiting point, so the satellite's trajectory is more flexible. The geometrical properties, formation maintenance strategy, and impulse-control solution for both models are investigated in detail. Finally, numerical simulations are conducted to verify the advantages of the proposed methods over other conventional methods, suggesting their wide applications in practical space missions. • Two impulsive-control models are proposed for bounded hovering formation in elliptical orbit. • The proposed methods support in-plane, out-of-plane, and three-dimension hovering formations. • The in-plane and out-of-plane controls are decoupled to decrease control complexity and difficulty. • Different factors on the fuel cost are analyzed to provide a reference for practical engineering. [ABSTRACT FROM AUTHOR]

Previous studies have shown that as L2 writing develops from intermediate to advanced levels, addition is marked less often and the use of and decreases as the use of moreover, furthermore and other less frequent addition markers increases. This study goes further in that it examines first how addition is marked in different academic disciplines and genres, and secondly how addition markers and their collocates are used by Chinese students in comparison to L1 writers of English. For the first question, and in contrast to Peacock's (2010) analysis of research articles, addition markers are used more in this student writing in the sciences of Engineering, Food Sciences and Biology than in the social sciences of Business and Law, and more in the more scientific writing of lab report genres than the discursive writing of essays. Such variation reinforces the importance of genre and discipline differences in teaching second language writing. For the second question, a qualitative analysis reveals the important difference between stringing several points using addition markers and grouping points into one argument using a shell noun, or reinforcing one argument with collocates. These findings lead to specific suggestions for L2 academic writing teachers. • Compares use of addition markers by genre and discipline. • Examines use of addition markers by Chinese students in English. • Deploys closely matched corpus of successful student writing in English. [ABSTRACT FROM AUTHOR]

• 2D MoTe 2 nanosheets were fabricated and characterized. • A sub-nanosecond IOPO pumped by a hybrid Q-switched laser has been realized. • Simulation results agreed with the experimental results well. In this paper, few-layered molybdenum ditelluride (MoTe 2) nanosheets are synthesized with a liquid-phase exfoliation method. Its appearance, the spectra and the saturated absorption characteristics are measured. By using MoTe 2 as saturable absorber (SA), a passively Q-switched YVO 4 /Nd:YVO 4 laser is realized. At an incident pump power of 6.64 W, a maximum output power of 1.14 W with a minimum pulse duration of 66.2 ns is obtained. To our knowledge, this is the shortest pulse width ever achieved from a passively Q-switched laser with a MoTe 2 -SA at 1.06 μm. Based on this, a sub-nanosecond KTiOPO 4 (KTP) based intracavity optical parametric oscillation (IOPO) pumped by a hybrid Q-switched laser with a MoTe 2 -SA and an acousto-optic modulator (AOM) is realized. At an incident pump power of 10.4 W and an AOM repetition rate of 10 kHz, a maximum output power of 195 mW with a minimum pulse duration of 835 ps for signal wave is obtained. To solve the IOPO rate equations, the ground-state and excited-state absorption cross sections of MoTe 2 are rationally calculated to be 1.32 × 10−18 cm2 and 9.15 × 10−19 cm2 according to the observed transmittance curve, respectively, and the excited-state lifetime is 376.2 µs. The numerical solution of the equations matches well with the experimental data. [ABSTRACT FROM AUTHOR]

Organic solvent nanofiltration (OSN) offers an energy-efficient alternative to conventional thermal distillation processes for organic solvent separations. However, the fabrication of polymeric OSN membranes with adequate chemical stability in strong polar aprotic solvents remains a remarkable challenge. In this work, chemically robust polyamide thin-film composite (TFC) OSN membranes were fabricated by utilizing an innovative chemical modification of polyimide (PI) nanofiber substrate via one-step crosslinking and thermal cyclodehydration of terephthalic hydrazide (TPDH). The crosslinking and cyclodehydration reaction mechanisms were thoroughly elucidated and the effects of TPDH loading and thermal treatment conditions on solvent resistance and pore structure of the resulting TPDH/PI nanofiber substrates as well as the formation of the polyamide selective layer were systematically studied. The resulting TFC membranes show excellent stability in polar aprotic solvents (i.e., DMF, DMAC, and NMP), and a high DMF permeance of 9.4 L m−2 h−1 bar−1 was achieved with a 99.8% rejection to Rose Bengal at 2.0 bar. The outstanding long-term performance stability revealed the robust structure of the developed TFC OSN membranes. This work demonstrates a facile strategy to address the chemical stability limitations of TFC OSN membranes through a multifaceted yet generalizable approach of chemical crosslinking and thermal cyclodehydration. We believe this strategy can be broadly applied to different substrates, enabling TFC membranes to address a wide variety of unmet OSN needs. (TFC membranes with chemically robust TPDH/PI nanofiber substrates for polar solvent filtration). [Display omitted] • Polyimide (PI) nanofiber substrate was chemically crosslinked by terephthalic dihydrazide (TPDH). • Thermal cyclodehydration further improves the chemical robustness of the crosslinked TPDH/PI nanofiber substrates. • The modified TPDH/PI nanofiber substrates show outstanding stability in polar aprotic solvents. • The resulting polyamide TFC membranes exhibit excellent performance in organic solvent filtration. [ABSTRACT FROM AUTHOR]

Endoglucanases provide an attractive avenue for the bioconversion of lignocellulosic materials into fermentable sugars to supply cellulosic feedstock for biofuels and other value-added chemicals. Thermostable endoglucanases with high catalytic activity are preferred in practical processes. To improve the thermostability and activity of the thermostable β-1,4-endoglucanase CTendo45 isolated from the thermophilic fungus Chaetomium thermophilum , structure-based rational design was performed by using site-directed mutagenesis. When inactivated mutation of the unique N-glycosylation sequon (N88-E89-T90) was implemented and the conserved Y173 residue was substituted with phenylalanine, a double mutant T90A/Y173F demonstrated enzymatic activity that dramatically increased 2.12- and 1.82-fold towards CMC-Na and β-D-glucan, respectively. Additionally, T90A/Y173F exhibited extraordinary heat endurance after 300 min of incubation at elevated temperatures. This study provides a valid approach to the improvement of enzyme redesign protocols and the properties of this endoglucanase mutant distinguish it as an excellent candidate enzyme for industrial biomass conversion. [ABSTRACT FROM AUTHOR]

Fly-around technology, as applied to maintain a chasing spacecraft flying periodically around the chief spacecraft, has received widespread attention in recent years. The conventional impulsive or continuous-thrust control approaches for maintaining non-natural formations put a high demand on the engine and limit the applicability of engineering. In this study, which is based on the relative orbital elements, we propose a series of analytic natural fly-around formations for the two-body case, which can revisit specific points or be maintained within a certain range. In addition to maintaining the fly-around formation when considering the J2 perturbation, we present a two-stage constant thrust control method solved with the linearized sensitive matrix. Furthermore, based on this method, we present several maintaining strategies that guarantee a periodic revisit to a specified relative position. We conduct numerical simulations to demonstrate the efficacy of these proposed methods. • A series of analytic natural fly-around formations are proposed. • The reference orbit is elliptical orbit, which can also be applied to circular orbit. • A two-stage constant thrust control method solved through the linearized sensitive matrix is presented. • Several maintaining strategies are presented to guarantees periodic revisit specified relative position. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effects of maternal exposure bisphenol A (BPA) on ovaries development of F1 female mice. The BPA exposure model of pregnant mice was prepared by intragastric administration of BPA at the doses of 0, 2.5, 5, 10, 20, 40 mg kg−1 d−1 at gestation day (GD) 0.5–17.5. The ovarian index of the offspring mice was calculated at postnatal day (PND) 21 and PND 56. The results showed that BPA at 5 mg/kg, 10 mg/kg, 20 mg/kg and 40 mg/kg significantly increased the abortion rate of the pregnant mice, and each dose of BPA significantly reduced the survival rate of the pups (P < 0.01 or P < 0.05). Besides, there was a non-monotonic dose-response relationship between serum hormone, ovarian receptor levels and BPA in F1 females at both PND 21 and 56. BPA increased the ovarian/uterine index in F1 females at both PND 21 and 56, increased the mRNA relative transcript levels of ovarian ERα, PgR and DNA methyltransferase (DNMT) in F1 females at PND 21, while decreased at PND 56 (P < 0.01 or P < 0.05). BPA also increased the relative expression of caspase-7, caspase-9, bax, inhibited the relative expression of bcl-2 in F1 females at both PND 21 and 56, and increased the apoptosis rate in the ovaries in F1 mice at PND 56 (P < 0.01). The number of follicles in the ovary was increased in F1 females at PND 21, and the ovaries were significantly atrophied when sexual maturity (PND 56). Our results indicated that BPA could disturb the contents of DNMT and make reproductive injury to the offspring females. • BPA causes apoptosis and methylation in female ovaries. • BPA interferes with ovarian development. • BPA incurs ovarian dysfunction. [ABSTRACT FROM AUTHOR]

For the visibility optimization problem of satellite constellations, this paper presents an efficient hybrid optimization method taking multiple constraints into account. To reduce the time needed for the optimization, the satellite constellation is assumed to have a specific configuration. The optimization includes two steps. The first step searches for optima over a large scale, while the second step is designed to obtain the accurate optimal solution based on the result of the first-step optimization. Based on the analysis of the coverage performance function, a linear adaptive population method is proposed for the first step. When compared with the traditional optimization method, calculation time can be efficiently reduced while ensuring an accurate optimization. Several numerical simulations are conducted for validation. It proves to be a practical choice for engineering applications. • Different types of satellite load sensors and different coverage performance indices are considered. • Constraints of double- or more-level coverage are discussed. • The trend of the number of local maximum points of one-level coverage to the ground point are analyzed. • A novel hybrid two-step optimization method is proposed. [ABSTRACT FROM AUTHOR]

This study investigated the effects of Salvia miltiorrhiza polysaccharides (SMPs) on the injury of chicken hepatocytes in vitro and in vivo. In in vitro studies primary cultured hepatocytes were isolated by 2-step collagenase perfusion. Carbon tetrachloride (CCL4) was added to the hepatocytes to establish a hepatocyte injury model. Hepatocytes were treated with different concentrations of SMPs to detect the protective effects of SMPs on CCL4-induced hepatocyte injury. The results of the control group showed that chicken hepatocytes grew well and their morphology was normal. After CCL4 treatment, the activity of alanine transaminase (ALT) and aspartate transaminase (AST) of hepatocytes increased compared with the normal control group. SMPs treatment downregulated the contents of ALT, AST, and malondialdehyde (MDA), and upregulated the contents of glutathione (GSH) and cytochrome P 450 (CYP450). An acute chicken liver injury model was established in vivo with 2.0 mL/kg 50% CCL4. Oral administration of SMP at different doses exhibited preventive success. The results showed that compared with the control group, the contents of total protein (TP), albumin (Alb), and GSH in the liver injury model group were significantly decreased and the levels of liver index, ALT, AST, and MDA were significantly increased. In contrast, in the SMP group the contents of TP, Alb, and GSH were significantly increased, and the levels of liver index, ALT, AST, and MDA were significantly decreased compared with the model group. Therefore, we conclude that SMPs have good protective effect on chicken liver damage in vivo and in vitro. [ABSTRACT FROM AUTHOR]

• Different flamelet tables can be generated by using the same laminar flamelet solutions. • Different flamelet table integration approaches can lead to different predictions. • Effect of table integration on a turbulent combustion flame is investigated. A flamelet model implementation consists of two steps: the generation of a set of laminar flamelet solutions and the integration of the laminar flamelet solutions with presumed shape probability density functions (PDFs) to produce a flamelet table for turbulent flame simulations. Many studies have been done in the past to examine the effect of different flamelet modeling strategies including the effect of employing different laminar flamelet solutions for the modeling. However, little work has been done to examine the effect of different presumed PDF table integration approaches on different flamelet model predictions. This work aims at investigating the source of errors arising from the flamelet table integration. The flamelet/progress variable model is chosen as a representative flamelet model, and three different presumed PDF table integration approaches are compared to examine the effect of table integration on flamelet model predictions. A laboratory-scale turbulent non-premixed jet flame (Sandia flame D) is chosen as a test case for the examination. In general, some evident sensitivity of the modeling results to the different flamelet table integration approaches is observed. The underlying reasons for the performance difference of different approaches are explored, and it is found that a model that preserves the one-dimensional laminar flamelet structure during the presumed-PDF table integration can improve the model prediction accuracy. Different sources of errors involved in flamelet model implementation are investigated, including numerical integration errors, flamelet table errors, and the errors in the predictions of the flamelet independent variables. [ABSTRACT FROM AUTHOR]

A new ternary zinc(II) coordination polymer [Zn 2 (bbmb) 2 (tdc) 2 ]·2H 2 O (CP 1) 1,4-bis(benzimidazol-1-yl-methyl)benzene(bbmb), 2,5-thiophenedicarboxylic acid (H 2 tdc) was hydrothermally synthesized and characterized by IR, elemental analysis and powder X-ray diffraction. CP 1 is a 3D 4-connected sra framework with the symbol point of {42,63,8} which possesses high sensitivity and selectivity as luminescence sensor for detected of Hg2+ ions in aqueous solution. Moreover, CP 1 possesses high photocatalytic activities for decomposed methylene blue (MB) under UV light irradiation. A Zn(II) ternary coordination polymer (CP 1) was synthesized under hydrothermal condition, CP 1 exhibit a 3D framework with unusual sra topology. The CP 1 displays highly efficiency response for Hg2+ ions and photodegradation activity for MB under UV irradiation. Unlabelled Image • An unusual 4-connected Zn(II) CP with sra topology was synthesized and characterized. • CP 1 show remarkable efficiency for photodegradation of MB. • CP 1 can be as a luminescent sensor for detection of Hg2+ ions. [ABSTRACT FROM AUTHOR]

The effect of AlCuMnFe IMPs on the corrosion behavior of 2050-T84 Al-Li alloy was investigated in NaCl solution. EBSD phase map illustrated that AlCuMnFe IMPs consisted of Al 7 Cu 2 Fe and Al 6 Mn, based on which the coupling system of the two phases and matrix was synthesized by Spark Plasma Sintering for simulating multi-phase AlCuMnFe IMPs. Corrosion of IMPs was accelerated after coupling Al 7 Cu 2 Fe and Al 6 Mn. First-principles calculations further elaborated the mechanism of the coupling effect in accelerating the corrosion of Al 6 Mn and improving the oxygen reduction reaction current on the surface of Al 7 Cu 2 Fe from the perspective of electronic structure and electron transfer. • Multi-phase AlCuMnFe IMPs in 2050 Al-Li alloy consist of Al 7 Cu 2 Fe and Al 6 Mn. • Corrosion resistance of Al 6 Mn decreases after coupling. • Coupling effect favors the oxygen reduction reaction on the surface of Al 7 Cu 2 Fe. • Electronic structural and charge transfer affect the corrosion of alloys. [ABSTRACT FROM AUTHOR]

Twelve formyl phloroglucinol meroterpenoids (FPMs) were isolated from the leaves of Eucalyptus robusta Smith. Their structures were elucidated via spectroscopic data analysis, the circular dichroism (CD) exciton chirality method, Rh 2 (OCOCF 3) 4 -induced CD experiments, and application of the Snatzke chirality rules. Eucalrobusones Q, S, and X are the first FPMs that have been identified in which the C-7′ of phloroglucinol is linked to the C-15 of cadinane, the C-4 of cubebane, and the C-8 of menthane, respectively. (+)-Eucalrobusone X exhibited the most potent antifungal ability against Candida albicans with a MIC 50 value of 10.78 μ g/mL, and eucalrobusone U exhibited the greatest anti- C. glabrata activity with MIC 50 value of 1.53 μ g/mL. As a result of investigating antifungal formyl phloroglucinol meroterpenoids (FPMs), twelve FPMs including three undescribed carbon skeletons were isolated from the leaves of Eucalyptus robusta. Image 1 • Twelve formyl phloroglucinol meroterpenoids (FPMs) were isolated from Eucalyptus robusta. • The carbon skeletons of compounds 1 , 3 , 9 , and 10 are reported here for the first time. • FPMs were determined by CD exciton chirality method, Rh 2 (OCOCF 3) 4 -induced CD experiment, and the Snatzke chirality rules. • Some FPMs exhibited significant antifungal activities against Candida glabrata and C. albicans. [ABSTRACT FROM AUTHOR]

The goal of this paper is to investigate the on-orbit servicing (OOS) of geosynchronous satellites based on low-thrust transfers while considering the different demands of the satellites and the effects of perturbations. One or more servicing spacecraft start from a parking orbit and service the satellites in sequence via low-thrust orbit transfers, and return to the parking orbit in the end. The different demands lead to different service requirements of time and mass, while the perturbations affect the control solution of servicing spacecraft during each transfer, and induce orbit drifts of uncontrolled target satellites during the mission. An analytical method that can efficiently calculate the fuel consumption of low-thrust transfer is proposed, and methods for evaluating the orbit drifts of uncontrolled satellites are presented. The impact of perturbations on OOS mission is investigated in detail, showing that non-negligible factors include lunisolar attraction and tessral harmonic. Based on the dynamic models, a string-based simulated annealing algorithm is adopted to schedule the OOS mission. The efficiency of the proposed dynamic models and optimization method are verified through ample simulations. Results show that it is much more efficient and reasonable to take orbit drift calculations as corrections on the scheduling result assuming no orbit drifts. The proposed models and methods make it possible to schedule the OOS mission with low-thrust transfers, while achieving high accuracy under the effects of J2 perturbation, lunisolar attracion, tesseral harmonic and solar radiation pressure. • On-orbit servicing (OOS) of GEO satellites via low-thrust transfers is studied. • Analytical transfer solution is developed to calculate the fuel consumption. • J2, lunisolar attraction and tesseral harmonic affect fuel consumption of OOS. • Various servicing demands lead to different requirements of time and cargo mass. • A string-based simulated annealing algorithm is designed to schedule the OOS mission. [ABSTRACT FROM AUTHOR]

Abstract When compared with Cartesian coordinates, curvilinear coordinates have shown significant superior accuracy when applied to a linear model for relative motion in a circular reference orbit. Experts assume the same superiority for an elliptical reference orbit. However, the curvilinear model in an elliptical reference orbit has not been established, and the superiority has not been proved. After a strictly theoretical derivation this paper establishes a linear model with spherical coordinates for relative motion in an elliptical reference orbit. The differential equation has the same form as the Lawden or Tschauner-Hempel equation and can be easily solved with the solutions from the literature. In addition both the theoretical derivation and the numerical examples prove the model's superior accuracy in leader-follower formation and formations with a large along-track distance. The proposed model reduces the approximate limits of close relative motion, and it is expected to be applied in the propagation, guidance, and control for longer term relative motion with large along-track distances. [ABSTRACT FROM AUTHOR]

Abstract This study focuses on the Mesozoic–Cenozoic tectono-thermal events in the Central Uplift of the South Yellow Sea Basin (SYSB) based on the CSDP-2 borehole. CSDP-2 is the first borehole to penetrate the integrated Paleozoic–Mesozoic sedimentary strata and recovered approximately 2736 m of core. The drilling results confirm a significant stratigraphic hiatus, i.e., Indosinian unconformity, between the Neogene–Quaternary and the underlying Lower Triassic. The eroded thickness estimated from sonic log and vitrinite reflectance data range from ∼1200 to 1400 m. Multiple paleo-thermometer data from the CSDP-2 cores, including vitrinite reflectance, apatite/zircon fission-track (AFT/ZFT) and fluid inclusions, were used to reconstruct the Mesozoic–Cenozoic thermal history in the study area. There was a continuous heating process during the early Mesozoic. The peak paleo-temperature may have reached up to 160 °C (base Permian) during the Late Jurassic, with the highest paleo-geothermal gradient of approximately 58.8 °C·km−1. The tectono-thermal evolution was dominated by the Mesozoic intracontinental collision between the Yangtze Craton and the Sino-Korean platform. The heating process was mainly caused by rapid burial on the passive continental margin and igneous activities. The paleo-temperature significantly decreased following the Late Jurassic. Two rapid cooling processes ca. 100–65 Ma and ca. 35 Ma are suggested by the AFT modeling results. Cooling history indicates that the tectonic uplift and denudation likely occurred from the Early Cretaceous to the Miocene. The reconstruction results of thermal evolution confirm that the Mesozoic–Paleozoic source rocks are mature or even highly mature, and hydrocarbon generation, migration and charge undoubtedly occurred in the Central Uplift, showing substantial hydrocarbon potential. Moreover, the reconstruction of the tectono-thermal history provides important constraints for regional tectonic studies. Highlights • Mesozoic–Cenozoic tectono-thermal events in the Central Uplift of the South Yellow Sea Basin was discussed. • Tectono-thermal history was reconstructed based on multiple paleo-thermometer data from the CSDP-2 borehole. • Substantial hydrocarbon potential in the marine deposits in the SYSB was confirmed. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Dual sustained drug release system was designed by a facile strategy. • Biocompatible and mesoporous Fe 3 O 4 −COOH nanoparticles were synthesized for designing drug carrier. • Improved mechanical performance and sustained drug release behavior were achieved. Abstract A facile strategy to incorporate dual sustained-release system in electrospun poly(lactic acid) (PLA) nanofibers is proposed for emerging applications in advanced drug delivery. Firstly, a model antimicrobial therapeutics, tetracycline hydrochloride (TCH) was blended with Fe 3 O 4 -COOH nanoparticles via electrostatic interaction to form novel composite nanoparticles. Then the influence of Fe 3 O 4 -COOH or TCH/Fe 3 O 4 -COOH nanoparticle incorporation on the morphology, porosity and hydrophilicity of electrospun PLA nanofiber membranes were elucidated. By studying drug release profiles, the newly designed TCH/Fe 3 O 4 -COOH/PLA nanofibrous membrane exhibited an obvious transition of drug release mechanisms from zero order release kinetics within the initial 6 days to modulated release beyond 6 days (until 14 days) in PBS. In contrast, TCH/Fe 3 O 4 -COOH and TCH/PLA nanofibrous membrane display single mechanism of burst like release within 3.5 days and 2.5 days, respectively. The Young's modulus, tensile strength and toughness of TCH/Fe 3 O 4 -COOH/PLA nanofibers are increased by 191%, 150% and 223%, respectively, compared with those of plain PLA electrospun nanofibers. Most importantly, TCH/Fe 3 O 4 -COOH/PLA nanofibrous membrane exhibited significantly stronger antibacterial activities against E. coli and S. aureus compared to TCH/Fe 3 O 4 -COOH and TCH/PLA nanofibrous membrane. The improved mechanical performance and sustained drug release behavior on TCH/Fe 3 O 4 -COOH/PLA pave the way for the emerging applications in drug delivery and tissue engineering. [ABSTRACT FROM AUTHOR]

The viewpoint that radial oxygen loss (ROL) of submerged macrophytes induces changes in redox conditions and the associated phosphorus (P) availability has been indirectly confirmed at larger spatial scales using conventional, destructive techniques. However, critical information about microniches has largely been overlooked due to the lack of satisfactory in situ mapping technologies. In this study, we deployed a recently developed hybrid sensor in the rhizosphere of Vallisneria spiralis ( V. spiralis ) during two vegetation periods to provide 2-D imaging of the spatiotemporal co-distribution of oxygen (O 2 ) and P from a fixed observation point. Overall, the images of O 2 and P showed a high degree of spatiotemporal heterogeneity throughout the rhizosphere at the sub-mm scale. A clear decrease in the P mobilization corresponded well to the steep O 2 enhancement within a 2-mm - thick zone around younger V. spiralis root, indicating a significant coupling relationship between ROL and P availability. Surprisingly, despite significant diurnal shifts in ROL along the older V. spiralis roots, P availability did not fluctuate in a substantial part of the rhizosphere throughout the day; however, ROL increased the P immobilization significantly by changing the redox gradients at the outer rhizosphere. This study clearly demonstrates how continuous ROL of V. spiralis can play a major role in regulating P availability within the rhizosphere. The premise behind this statement is the discovery of how this continuous ROL can lead to the formation of three distinctive redox landscapes in the rooting sediment (oxic, suboxic, or anaerobic layers). [ABSTRACT FROM AUTHOR]

Enzymatic saccharification of lignocellulosic biomass is increasingly applied in agricultural and industrial applications. Nevertheless, low performance in the extreme environment severely prevents the utilization of commercial enzyme preparations. To obtain cellobiohydrolases with improved catalytic activity and thermostability, structure-based rational design was performed based on a thermostable cellobiohydrolase CtCel6 from Chaetomium thermophilum . In the present study, four conserved and noncatalytic residue substitutions were generated via site-directed mutagenesis. Mutations were heterologously expressed in yeast Pichia pastoris , purified, and ultimately assayed for enzymatic characteristics. The mutant Y119F increased the catalytic activity 1.82-, 1.65- and 1.43-fold against β- d -glucan, phosphoric acid swollen cellulose (PASC) and carboxymethylcellulose sodium (CMC-Na), respectively. In addition, S131 W effectively enhanced the enzyme's heat resistance to elevated temperatures. The half-life (t 1/2 ) of this mutant enzyme was increased 1.42- and 2.40-fold at 80 °C and 90 °C, respectively, compared to the wild-type. This study offers initial insight into the biological function of the conserved and noncatalytic residues of thermostable cellobiohydrolases and provides a valid approach to the improvement of enzyme redesign proposal. [ABSTRACT FROM AUTHOR]

One of the productive lines of research on self-assessment (SA) and peer assessment (PA) concerns their concurrent validity with respect to a criterion measure. However, similar research has rarely been conducted for spoken-language interpreting. This article therefore reports on a longitudinal study that investigated the validity of self and peer ratings on three performance dimensions of English-Chinese consecutive interpretation (i.e., information completeness, fluency of delivery, and target language quality), taking teachers’ ratings as a yardstick. Major findings include: although the students as a group were unable to replicate teachers’ ratings, they were able to rank-order their performances in a fairly accurate manner and improved their SA and PA accuracy over time. Interpreting directionality seems to moderate the correlational strength of self/teacher ratings and peer/teacher ratings. These results are discussed in relation to previous literature, and pedagogical suggestions are provided to improve SA and PA for bi-directional interpretation. [ABSTRACT FROM AUTHOR]

Countercurrent chromatography (CCC) has gradually become a widely used method for preparative separation of bioactive natural molecules. These molecules generally contain distinct scaffolds and characteristics that cannot be readily isolated from plants. While one-dimensional CCC is typically used for the initial purification with insufficiently resolved peaks after locating bioactive components, two-dimensional (2D) or multi-dimensional CCC strategies are employed to improve the resolution of peaks. However, these methods usually present certain disadvantages, such as complicated procedures and increased time consumption, experimental costs, and equipment requirements. Here, a bioactivity-guided cut CCC strategy was established to isolate lysine-specific demethylase 1 (LSD1) inhibitors from Scutellaria baicalensis Georgi. Gradient-elution CCC coupled with real-time detection of LSD1 inhibition by the collected fractions was developed. Next, an online-storage recycling CCC mode was designed to enable the active fractions to be stored in coils, and these active fractions were further separated to obtain pure compounds by using sequential recycling elution. In this strategy, active fractions are first identified, and then pure LSD1 inhibitors are isolated in the 2D CCC mode through continuous separation on a single instrument. By using our bioactivity-guided cut CCC strategy, we successfully isolated six natural LSD1 inhibitors from S. baicalensis Georgi, five of which were identified for the first time as natural LSD1 inhibitors. [ABSTRACT FROM AUTHOR]

Phosphite (P +III ) is of emerging chemical interest due to its importance within the global phosphorus cycle. Yet, to date, precise/accurate measurements of P +III are still lacking due to the inherent analytical challenges linked to its instability/ease of oxidation and ultra-trace concentration. Here, we present the first in-situ sampling and speciation analysis method, for dissolved P +III , using the diffusive-gradients-in-thin-films (DGT) technique, combined with capillary-column-configured-dual-ion-chromatography (CC-DIC). Method optimization of the DGT elution regime, to simultaneously maximize desorption efficiency and CC-DIC sensitivity, along with the characterization of diffusion coefficients for P +III , were undertaken before full method validation. Laboratory-performance testing confirmed DGT-P +III acquisition to be independent of pH (3.0–10.0) and ionic strength (0–500 mM). The capacity for P +III was 45.8 μg cm −2 , while neither P +V (up to 10 mg L −1 ) nor As +V (up to 1 mg L −1 ) impacted the DGT-P +III measurement. This novel method's functionality stems from the herein confirmed speciation preservation and double pre-concentration of P +III , resulting in quantification limits as low as 7.44 ng L −1 for a 3-day deployment. Applications of this method in various terrestrial/aquatic environments were demonstrated and simultaneous profiles of P +III and P +V across a sediment-water interface were captured at mm resolution in two contrasting redox-mesocosm systems. [ABSTRACT FROM AUTHOR]

In order to study the anti-inflammatory activity of novel 6-substituted and 6,9-disubstituted purine derivatives, 20 compounds, L1–10 and W1–10, derived from purine and lacking a gold complex were designed, synthesized and their anti-inflammatory activity was screened. LPS-induced TNF-α, IL-1β, IL-6, PGE2, NO, COX-2 and iNOS mRNA were evaluated, and western blot and NF-κB p65 translocation assay were performed in RAW 264.7 macrophages. Furthermore, carrageenan-induced hind paw edema experiments were performed in mice. Compound L1, L4, W2, and W4 markedly exerted a dose-dependent inhibition of TNF-α, IL-1β, IL-6 and PGE2 release induced by LPS in RAW 264.7 macrophages. Moreover, these compounds strongly inhibited LPS-induced NO, COX-2 and iNOS mRNA in the same cells. Anti-inflammatory activity tests in vivo showed that L1 and L4 were more effective than Au(L 3 )(PPh 3 ), a known anti-inflammatory agent, at 2–5 h, and W4 was the most effective at 3–5 h after dosing. Thus, W2, W4, and L1, L4, could effectively inhibit LPS-induced inflammatory response in vitro and in vivo suggesting a promising role as anti-inflammatory agents. [ABSTRACT FROM AUTHOR]

Cu(II) ion was selected as an additive to improve the enantioseparation efficiency of three dihydroflavone enantiomers in high-speed counter-current chromatography (HSCCC), using hydroxypropyl-β-cyclodextrin (HP-β-CyD) as the chiral selector. The influences of important parameters, including the metal ion, the concentrations of HP-β-CyD and the Cu(II) ion, and the sample size were investigated. Under optimal conditions, three dihydroflavone enantiomers, including (±)-hesperetin, (±)-naringenin, and (±)-farrerol, were successfully enantioseparated. The chiral recognition mechanism was investigated. The enantioseparation was attributed to the different thermodynamic stabilities of the binary complexes of HP-β-CyD and (±)-hesperetin, and Cu(II) ion could enhance this difference by forming ternary complexes with the binary complexes. This Cu(II) ion-improved complexation HSCCC system exhibited improved performance for chiral separation, and therefore it has great application potential in the preparative enantioseparation of other compounds with similar skeletons. [ABSTRACT FROM AUTHOR]

An iteration and superposition encryption scheme for image sequences based on multi-dimensional keys is proposed for high security, big capacity and low noise information transmission. Multiple images to be encrypted are transformed into phase-only images with the iterative algorithm and then are encrypted by different random phase, respectively. The encrypted phase-only images are performed by inverse Fourier transform, respectively, thus new object functions are generated. The new functions are located in different blocks and padded zero for a sparse distribution, then they propagate to a specific region at different distances by angular spectrum diffraction, respectively and are superposed in order to form a single image. The single image is multiplied with a random phase in the frequency domain and then the phase part of the frequency spectrums is truncated and the amplitude information is reserved. The random phase, propagation distances, truncated phase information in frequency domain are employed as multiple dimensional keys. The iteration processing and sparse distribution greatly reduce the crosstalk among the multiple encryption images. The superposition of image sequences greatly improves the capacity of encrypted information. Several numerical experiments based on a designed optical system demonstrate that the proposed scheme can enhance encrypted information capacity and make image transmission at a highly desired security level. [ABSTRACT FROM AUTHOR]

Spaceborne Global Positioning System (GPS) receivers are widely used for orbit determination of low-Earth-orbiting (LEO) satellites. With the improvement of measurement accuracy, single-frequency receivers are recently considered for low-cost small satellite missions. In this paper, a Schmidt-Kalman filter which processes single-frequency GPS measurements and broadcast ephemerides is proposed for real-time precise orbit determination of LEO satellites. The C/A code and L1 phase are linearly combined to eliminate the first-order ionospheric effects. Systematic errors due to ionospheric delay residual, group delay variation, phase center variation, and broadcast ephemeris errors, are lumped together into a noise term, which is modeled as a first-order Gauss-Markov process. In order to reduce computational complexity, the colored noise is considered rather than estimated in the orbit determination process. This ensures that the covariance matrix accurately represents the distribution of estimation errors without increasing the dimension of the state vector. The orbit determination algorithm is tested with actual flight data from the single-frequency GPS receiver onboard China’s small satellite Shi Jian-9A (SJ-9A). Preliminary results using a 7-h data arc on October 25, 2012 show that the Schmidt-Kalman filter performs better than the standard Kalman filter in terms of accuracy. [ABSTRACT FROM AUTHOR]

The magnetically suspended momentum wheel (MSMW) expands its fresh functions through deflecting the rotary shaft. An improved nonsingular terminal sliding-mode control (NTSMC) method is proposed to achieve high precision tracking of shaft deflection for the MSMW under coupled disturbance and saturated amplifier. A novel structure designed for this MSMW is introduced initially. Its magnetic torque model and coupled disturbance are analyzed, and a tracking error dynamic model is established. Then a NTSMC method is applied to shaft tracking control. As the saturation of amplifier influences tracking performances, an improved NTSMC is designed to deal with saturation problem. Finally, several simulations are performed to validate the effectiveness of the proposed method. The results indicate the proposed method improves the tracking precision and velocity compared with the conventional integral sliding-mode method, and solves the saturation problem compared with existing NTSMC method. [ABSTRACT FROM AUTHOR]

Background: Pain management after open hysterectomy has been investigated for years. Owing to the effect of significant analgesic, gabapentin was often administrated for pre-emptive analgesia. However, the relationship between gabapentin and postoperative pain after open hysterectomy is still controversial. This meta-analysis was applied to assess the efficacy of pre-emptive use of gabapentin in open hysterectomy.Methods: This meta-analysis of randomized controlled trials (RCTs) was performed to compare the use of gabapentin with placebo in open hysterectomy regarding (1) the mean difference (MD) of postoperative opioid requirements; (2) the changes of visual analogue scale (VAS) scores in two groups; and (3) incidence rate of adverse effects. Systematic searches of all related literatures was conducted using the following databases: MEDLINE, EMBASE, ClinicalTrials.gov and Web of Science. Only randomized controlled trials (RCTs) for open hysterectomy were included. The MD of postoperative opioid requirements and VAS scores, relative risk (RR) of incidence rate of adverse effects in the gabapentin group versus placebo group were extracted throughout the study.Results: Fourteen trials were included in this meta-analysis. The total opioid consumption at 24h was a less in gabapentin group. (MD=-11.61, 95% CI: -16.71 to -6.51, P=0.00) The visual analogue scale (VAS) score at 4, 12 and 24h were less in the gabapentin group. (MD=-16.83, 95% CI: -22.88 to -10.77, P=0.00), (MD=-17.45, 95% CI: -21.83 to -13.08, P=0.00), (MD=-9.83, 95% CI: -13.31 to -6.35, P=0.00) The incidence rate of vomiting and nausea were significantly less in gabapentin groups. (RR 0.13, 95% CI 0.45 to 0.73, P=0.00), (RR 0.67, 95% CI 0.49 to 0.93, P=0.02). Compared with placebo, gabapentin achieved higher patient satisfaction. (MD=20.43, 95% CI: 12.42 to 28.44, P<0.00).Conclusion: This meta-analysis suggested that the employment of gabapentin was efficacious in reduction of postoperative opioid consumption, VAS score and some side effects after open hysterectomy. [ABSTRACT FROM AUTHOR]

Precise (sub-meter level) real-time navigation using a space-capable single-frequency global positioning system (GPS) receiver and ultra-rapid (real-time) ephemerides from the international global navigation satellite systems service is proposed for low-Earth-orbiting (LEO) satellites. The C/A code and L1 carrier phase measurements are combined and single-differenced to eliminate first-order ionospheric effects and receiver clock offsets. A random-walk process is employed to model the phase ambiguities in order to absorb the time-varying and satellite-specific higher-order measurement errors as well as the GPS clock correction errors. A sequential Kalman filter which incorporates the known orbital dynamic model is developed to estimate orbital states and phase ambiguities without matrix inversion. Real flight data from the single-frequency GPS receiver onboard China's SJ-9A small satellite are processed to evaluate the orbit determination accuracy. Statistics from internal orbit assessments indicate that three-dimensional accuracies better than 0.50 m and 0.55 mm/s are achieved for position and velocity, respectively. [ABSTRACT FROM AUTHOR]

An fcc-bcc heterostructure is introduced in-situ by the phase separation of FeCoNi nanoparticles. The resulted structure exhibits significant enhancement in the multi-catalytic activity in the aqueous condition. [Display omitted] • Pyrolysis of Prussian blue precursors leads to nanosized CoFeNi electrocatalyst. • CoFeNi nanoparticles contain heterostructure formed in-situ. • Heterostructure enhances the tri-functional catalytic activity in various media. All-in-one transition metal-based electrocatalysts with high activities towards different reactions in aqueous electrolytes are of critical importance as they can dramatically bring down the cost of relevant energy devices. Herein a facile and low-cost synthesis of CoFeNi nanoparticles encapsulated by an N-doped carbon layer has been developed by pyrolyzing Prussian blue (PB) precursors. The obtained catalyst features tri-catalytic activity towards OER, ORR, and HER reactions in alkaline and acidic condition, and show great potential as a catalyst for water splitting and anode material for Zinc-Air batteries. Moreover, compared with the single phase, the sample with the heterostructure composed of both fcc and bcc phases exhibited dramatic enhancement in multi-catalytic activity. The heterostructure originates from an in-situ phase separation induced by composition variation. This demonstrates the effectiveness of heterostructure engineering introduced by in-situ phase separation in boosting the multi-catalytic activity. [ABSTRACT FROM AUTHOR]

Mercury is one of the most severe environmental pollutants due to its high toxicity, and the detoxification of mercury-containing solid wastes is a critical issue worldwide. In this work, thiosulfate solution has been used to leach mercury from mercuric sulfide. The influence of leaching conditions, including initial pH, molar ratio of copper to thiosulfate ([Cu]/[S 2 O 3 2− ]), and temperature on mercury leaching from mercuric sulfide, was investigated. The mercury leaching rate can reach as high as 92.37% after 7-h leaching under the optimized condition of initial pH 8.50, molar ratio of copper to thiosulfate 0.1 and leaching temperature 313 K. X-ray diffraction (XRD), scanning electron microscope-energy dispersive spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS) was used to analyze the leaching residue. The results show that copper in its thiosulfate complex can be substituted by mercury via Lewis substitution and cuprous sulfide was formed on the surface of leaching residue. The kinetics of mercuric sulfide leaching with cuprous-thiosulfate solutions was controlled by the product layer diffusion. [ABSTRACT FROM AUTHOR]

The effect of differential molecular diffusion (DMD) in turbulent non-premixed flames is studied by examining two previously reported DNS of temporally evolving planar jet flames, one with CO/H 2 as the fuel and the other with C 2 H 4 as the fuel. The effect of DMD in the CO/H 2 DNS flames in which H 2 is part of fuel is found to behave similar to laminar flamelet, while in the C 2 H 4 DNS flames in which H 2 is not present in the fuel it is similar to laminar flamelet in early stages but becomes different from laminar flamelet later. The scaling of the effect of DMD with respect to the Reynolds number Re is investigated in the CO/H 2 DNS flames, and an evident power law scaling (∼ Re − a with a a positive constant) is observed. The scaling of the effect of DMD with respect to the Damköhler number Da is explored in both laminar counter-flow jet C 2 H 4 diffusion flames and the C 2 H 4 DNS flames. A power law scaling (∼ Da a with a a positive constant) is clearly demonstrated for C 2 H 4 nonpremixed flames. [ABSTRACT FROM AUTHOR]

A novel instantaneous GNSS ambiguity resolution approach which makes use of only single-frequency carrier phase measurements for ultra-short baseline attitude determination is proposed. The Monte Carlo sampling method is employed to obtain the probability density function of ambiguities from a quaternion-based GNSS-attitude model and the LAMBDA method strengthened with a screening mechanism is then utilized to fix the integer values. Experimental results show that 100% success rate could be achieved for ultra-short baselines. [ABSTRACT FROM AUTHOR]

Long-term l -DOPA treatment of Parkinson’s disease is accompanied with fluctuations of motor responses and l -DOPA-induced dyskinesia (LID). Phosphorylation of the dopamine and c-AMP regulated phosphoprotein of 32 kDa (DARPP-32) plays a role in the pathogenesis of LID, and thus dephosphorylation of this protein by activated calcineurin may help reduce LID. One important activator of calcineurin is the Ca 2+ ionophore ionomycin. Here, we investigated whether intrastriatal injection of ionomycin to hemiparkinsonian rats produced changes in l -DOPA responses including LID. We also analyzed the effects of ionomycin on key molecular mediators of LID. Results confirmed our hypothesis that ionomycin could downregulate the phosphorylation of DARPP32 at Thr-34 and reduce LID. Besides, ionomycin decreased two established molecular markers of LID, FosB/ΔFosB and phosphorylated ERK1/2. Ionomycin also decreased the phosphorylation of three main subunits of the NMDA receptor, NR1 phosphorylated at ser896, NR2A phosphorylated at Tyr-1325, and NR2B phosphorylated at Tyr-1472. Furthermore, the anti-LID effect of striatally injected ionomycin was not accompanied by reduction of the antiparkinsonian action of l -DOPA. These data indicate that ionomycin largely interacts with striatal mechanisms that are critical to the l -DOPA motor response highlighting the role of protein dephosphorylation by calcineurin. [ABSTRACT FROM AUTHOR]

A novel sensor assembled by a hybrid film was developed for 2D combined measurements of DO dynamic and labile P flux in sediment and water at sub-millimeter resolution based on PO and DGT techniques. The hybrid film is comprised of a transparent polyester membrane supporting two ultrathin sensing layers, i.e., a P binding layer (PBL) overlying a DO sensing layer (DSL). A robust, straightforward measuring strategy based on the referenced RGB and coloration-computer imaging densitometry (CID) methods was developed. Sensing properties for DO show a considerable homogeneity (RSD < 5%) and rapid response (<24 s) in fluorescent response. Calibration experiments reveal the sensitivity values for the DSL without/with PBL are 2.12/1.95, with an acceptable bias of less than 8%. The optimized PBL possesses a uniform distribution of zirconium-oxide microparticles at a relatively high DGT capacity (10.8 μg P cm −2 ), in which the distribution of adsorbed-P can be imaged by the coloration-CID method. The performance of the sensor is compared to two conventional PO and DGT sensors. The hybrid sensor was successfully deployed in three types of benthic micro-interface and showed significant small-scale heterogeneity, providing new opportunities for advancing investigations into relevant biogeochemical processes. [ABSTRACT FROM AUTHOR]

A novel integrated model predictive iterative learning control (MPILC) strategy with dynamic R-parameter for batch processes is proposed in this paper. It systematically integrates batch-axis information and time-axis information into one uniform frame, namely the iterative learning controller (ILC) in the domain of batch-axis, while a model predictive controller (MPC)with time-varying prediction horizon in the domain of time-axis. As a result, the operation policy of batch process can be regulated during one batch, which leads to superior tracking performance and better robustness against disturbance and uncertainty. Moreover, both model identification and dynamic R-parameter are employed to eliminate the model-plant mismatch and make zero-error tracking possible. Next, the convergence and tracking performance of the proposed integrated model predictive learning control system are given rigorous description and proof. Lastly, the effectiveness of the proposed method is verified by one example. [ABSTRACT FROM AUTHOR]

Cu(II) complexed amino acid ionic liquid, Cu(II)-[1-butyl-3-methylimidazolium][L-Pro] (Cu(II)-[BMIm][L-Pro]), was successfully adopted as chiral ligand to improve the enantioseparation efficiency in high speed counter-current chromatography (HSCCC). For the enantioseparation of intractable naringenin (NRG) racemic mixtures, Cu(II)-[BMIm][L-Pro] coupled with hydroxypropyl-β-cyclodextrin (HP-β-CD) was successfully applied as dual chiral selectors in HSCCC. The influence of important parameters, including the concentration of the chiral selectors, the pH value, and the temperature were investigated. Under optimal conditions, 4.5 mg of (+)-NRG and 4.1 mg of (−)-NRG were successfully separated from 10 mg NRG racemic mixtures with the purity of 98%. The chiral recognition mechanism of dual chiral selectors was illuminated by the UV–vis and NMR spectra, suggesting that the enantioseparation was upon the difference of the thermodynamic stability of the quaternary complexes of Cu(II), [BMIm][L-Pro], HP-β-CD, and NRG. The results illustrated that the developed HSCCC system, based on the synergistic mechanism of Cu(II)-[BMIm][L-Pro] and HP-β-CD, exhibited better performance on enantioseparation and had great application potential in preparative chiral separation of natural products. [ABSTRACT FROM AUTHOR]

Oxygen (O 2 ) availability within the sediment–root interface is critical to the survival of macrophytes in O 2 -deficient sediment; however, our knowledge of the fine-scale impact of macrophyte roots upon the spatiotemporal dynamics of O 2 is relatively limited. In this study, a no n -invasive imaging technology was utilized to map O 2 micro-distribution around Vallisneria spiralis. Long-term imaging results gathered during a 36 day-period revealed an abundance of O 2 spatiotemporal patterns ranging from 0 to 250 μmol L − 1 . The root-induced O 2 leakage and consequent oxygenated area were stronger in the vicinity of the basal root compared to that found in the root tip. The O 2 images revealed V. spiralis exhibited radial O 2 loss (ROL) along the entire root, and the O 2 distribution along the root length showed a high degree of small-scale spatial heterogeneity decreasing from 80% at the basal root surface to 10% at the root tip. The oxygenated zone area around the roots increased as O 2 levels increased with root growth and irradiance intensities ranging from 0 to 216 μmol photons m − 2 s − 1 . A weak ROL measuring < 20% air saturation around the basal root surface was maintained in darkness, which was presumably attributed to the O 2 supply from overlying water via plant aerenchyma. The estimated total O 2 release to the rhizosphere of V. spiralis was determined to range from 8.80 ± 7.32 to 30.34 ± 17.71 nmol m − 2 s − 1 , which is much higher than many other macrophyte species. This O 2 release may be an important contribution to the high-capacity of V. spiralis for quickly colonizing anaerobic sediment. [ABSTRACT FROM AUTHOR]