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Cadmium (Cd) toxicity induce various disturbances in metabolic processes and impair plant establishment. The composition of carbon and nitrogen stable isotopes (δ

The discrete topology and sizing optimization of frame structures with compliance constraints is studied using a novel approach, which is capable of finding the theoretical lower bounds and high-quality discrete solutions in an efficient manner. The proposed approach works by reformulating the discrete problem as a relaxed semidefinite programming (SDP) problem. This reformulation is made possible by a linear relaxation of the original discrete space and the elimination of the nonconvex equilibrium equation using a semidefinite constraint. A continuous global optimum is first derived using existing solvers and then the discrete solution is discovered by the neighborhood search. Numerical examples are presented, including the sizing optimization of 2-Bay 6-Story frame and 3-Bay 10-Story frame, the topology and sizing optimization of 2-Bay 6-Story braced frame. A topology and sizing example with multiple load cases is also provided. The proposed approach and three other metaheuristic algorithms are used to solve these examples. Theoretical lower bounds for these examples can be efficiently discovered by the proposed approach. For the sizing problems, the discrete solutions by the proposed approach are all better than the other algorithms. For the topology and sizing problems, the proposed approach achieves discrete solutions better than genetic algorithm, but worse than the other metaheuristics. The computational superiority of the proposed approach is validated in all the examples.

Objectives The concrete mechanism underlying the pathogenesis of cervical vertigo has not been well illustrated. This study aims to determine the diagnostic and potential therapeutic values of the neurotransmitter neuropeptide Y (NPY) in cervical vertigo. Methods Sixty male rabbits were randomly divided into five groups: the blank control, superior cervical sympathetic ganglia (SCSG) stimulation, SCSG sham-operated control (ganglion exposure and electrode placement in SCSG), inferior cervical sympathetic ganglia (ICSG) stimulation, and ICSG sham-operated control (ganglion exposure and electrode placement in ICSG) groups. Electrical stimulation at 30.0 Hz and 10.0 V for 5 min was delivered to expose SCSG or ICSG. Immunochemistry was conducted to determine the expression levels of NPY in all cervical spinal ganglia (C1–C8) dissected immediately after electrical stimulation. Results According to the immunohistochemical results, the blank control group only had few NPY-positive cells and was not significantly different with the sham-operated group. However, after SCSG stimulation, more NPY-positive cells in C2, C3, C4, and C5 were observed (C2 and C3 were the most evident). After ICSG stimulation, more NPY-positive cells were found in C6, C7, and C8, particularly in C6 and C7. Conclusions The low expression of NPY in all cervical ganglia (C1–C8) can be enhanced by electrical stimulation, whereas the expression of NPY in the cervical sympathetic ganglia was not affected by mechanical stimulation. This study provided new insights into the possible relationship between the neurotransmitter NPY and the pathogenesis of cervical vertigo.

A magnetic field sensor based on Fabry–Pérot interferometer (FPI) with soft gold magnetic composite film (GMCF) is proposed and demonstrated experimentally. GMCF is fabricated by Fe3O4-doped polydimethylsiloxane (PDMS) film and adhered thin gold membrane via van der Waals force. Applying an external magnetic field, GMCF can vibrate under magnetic forces and cause a change in the cavity length of FPI and hence modulates the interference spectra. Experimental results indicate that the sensor can achieve maximum sensitivity of 390 pm mT−1 under a linear magnetic field intensity ranging from 0 to 65 mT. The proposed sensor could help with magnetic field detection in complex environments.

Facing the elevated surface summer O

Performance-based design optimization of steel frames, with element sections selected from standard sections, is a computationally intensive task. In this article, an efficient discrete optimization algorithm is proposed for performance-based design optimization of steel frames. The computational efficiency is improved by searching in a sensible manner, guided by the deformation information of structural elements. To include all standard sections in the design space, the cross-sectional area ( Area) and moment of inertia ( Ix) are selected as the design variables. Based on different relationships between Area and Ix, a twofold strategy is put forward, which includes a quick exploration and an elaborate exploitation. For comparison, a similar algorithm is also proposed, using Area as the only design variable. A fixed relationship between Area and other sectional properties is used. Two numerical examples are presented to minimize the structural weight while satisfying performance constraints. The results indicate that the proposed discrete algorithm can achieve lighter structural designs than the area-only algorithm. Furthermore, the convergence history proves that a high computational efficiency can be realized by using the proposed algorithm.

Methane (CH

S-polarization light and p-polarization light are mutually cross orthogonal, which can be used as signal light for emitting and receiving in the polarization-modulated space laser communication, respectively. Due to the retro reflection characteristics of the corner cube retroreflector (CCR), it is widely used as a calibration reflector system in the polarization-modulated space laser communication. The polarization states of the incident light will be change owing to the total internal reflection (TIR) of uncoated rear surface, in addition, each of the six propagation trips will in general produce a different output polarization. For the calibration reflector system in the polarization-modulated space laser communication, the polarization state of the received light, especially the intensity ratio of the p-polarization component, needs to be clarified. In this paper, a framework is presented to calculate polarization by ray tracing through CCR with arbitrary input polarization states and incident angles. On this basis, the relationships between intensity ratio of the p-polarization component in the received light of each propagation trip and the incident light with different polarization states at normal incidence as well as the circular polarized light at incident angles within ± 15°analyzed. Theoretical analysis and experiments have guiding significance for the development of the polarization-modulated space laser communication.

Methane (CH4) is the second most important greenhouse gas, contributing approximately 17% of radiative forcing, and CH4 emissions from river networks due to intensified human activities have become a worldwide issue. However, there is a dearth of information on the CH4 emission potentials of different rivers, especially those draining contrasting watershed landscapes. Here, we examined the spatial variability of diffusive CH4 emissions and discerned the roles of environmental factors in influencing CH4 production in different river reaches (agricultural, urban, forested and mixed-landscape rivers) from the Chaohu Lake Basin in eastern China. According to our results, the urban rivers most frequently exhibited extremely high CH4 concentrations, with a mean concentration of 5.46 μmol L−1, equivalent to 4.1, 9.7, and 7.2 times those measured in the agricultural, forested, and mixed-landscape rivers, respectively. The availability of carbon sources and total phosphorus were commonly identified as the most important factors for CH4 production in agricultural and urban rivers. Dissolved oxygen and oxidation-reduction potential were separately discerned as important factors for the forested and mixed-landscape rivers, respectively. Monte Carlo flux estimations demonstrated that rivers draining contrasting landscapes exhibit distinct potentials to emit CH4. The urban rivers had the highest CH4 emissions, with a flux of 9.44 mmol m−2 d−1, which was 5.1–10.4 times higher than those of the other river reaches. Overall, our study highlighted that management actions should be specifically targeted at the river reaches with the highest emission potentials and should carefully consider the influences of different riverine environmental conditions as projected by their watershed landscapes.

Research in electric double-layer capacitors (EDLCs) and rechargeable batteries is converging to target systems that have battery-level energy density and capacitor-level cycling stability and power density. This research direction has been facilitated by the use of redox-active electrolytes that add faradaic charge storage to increase energy density of the EDLCs. Aqueous redox-enhanced electrochemical capacitors (redox ECs) have, however, performed poorly due to cross-diffusion of soluble redox couples, reduced cycle life, and low operating voltages. In this manuscript, we propose that these challenges can be simultaneously met by mechanistically designing a liquid-to-solid phase transition of oxidized catholyte (or reduced anolyte) with confinement in the pores of electrodes. Here we demonstrate the realization of this approach with the use of bromide catholyte and tetrabutylammonium cation that induces reversible solid-state complexation of Br2/Br3–. This mechanism solves the inherent cross-diffusion i...

Purpose Spun silk is one of the top grade textile materials, and its products have high added value and meet the needs of the market. However, the technology level and process design of silk spinning are still much lower than cotton spinning; especially singeing is applied on spun silk yarn, and generates waste materials. The purpose of this paper is to introduce a kind of pneumatic compact spinning, four-line compact spinning (FLCS), into silk spinning and study the corresponding spun yarn qualities. Design/methodology/approach First, taking the silk spinning frame FK501 as an example, the process of modification of FLCS is presented. Then, three kinds of spun silk yarns, 80 Nm (12.5tex), 100 Nm (10tex) and 120 Nm (8.3tex), are spun on the common silk spinning frame FK501 and the spinning frame modified with FLCS. The evenness, breaking strength and hairiness of spun yarns are tested and comparatively analyzed. After the ply yarn production, three singeing procedures should be applied on the ring ply yarns, while only two singeing procedures should be applied on the compact ply yarns, which is beneficial for material saving. Findings The results show that compared with ring spun silk yarns, the comprehensive quality of compact spun silk yarns is improved, especially the harmful long hairiness (=3 mm) of yarn. Compared with the single spun silk yarn, the comprehensive qualities of the ply yarn are improved; especially, the breaking strength of the ply yarns is two times larger than the single yarn. After singeing, the hairiness of the ply yarn is decreased greatly, and the evenness is also improved, while the strength is decreased. Compared with ring spun silk yarn, the singeing times of compact spun silk yarn can be decreased, and the gas consumption in each singeing is also decreased, which is beneficial for material saving. Originality/value In this paper, a kind of pneumatic compact spinning, FLCS, is introduced into the silk spinning. It is shown that compared with ring spun silk yarns, the comprehensive quality of compact spun silk yarns is improved, especially the harmful long hairiness (=3 mm) of yarn. After the ply yarn production, three singeing procedures should be applied on the ring ply yarns, while only two singeing procedures should be applied on the compact ply yarns, which is beneficial for material saving.

To design container cranes with reliable performance levels under multiple seismic hazards, an approach is developed for performance-based design optimization (PBDO) of container cranes. First a simplified planar finite element model is built for container cranes. In order to mitigate the seismic responses, buckling restrained braces (BRB), instead of ordinary braces, are used in the model. Two performance criteria are considered and the deformations of structural elements are selected to define the performance criteria. The pattern search method is employed to efficiently solve the optimization task. The result indicates that the structural weight of container cranes can be remarkably reduced while satisfying multiple performance requirements. Conclusion can be drawn that the proposed approach is an efficient method for PBDO of container cranes.

We demonstrate for the first time that hydronium ions can be reversibly stored in an electrode of crystalline 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA). PTCDA exhibits a capacity of 85 mAh g−1 at 1 A g−1 after an initial conditioning process. Ex situ X-ray diffraction revealed reversible and significant structure dilation upon reduction of PTCDA in an acidic electrolyte, which can only be ascribed to hydronium-ion intercalation. The lattice expansion upon hydronium storage was theoretically explored by first-principles density functional theory (DFT) calculations, which confirmed the hydronium storage in PTCDA.

The rate capability of hard carbon has long been underestimated in prior studies that used carbon/Na two-electrode half-cells. Through a three-electrode cell setup, we discover that it is the overpotential of the sodium counter electrode that drives the half-cells to the lower cutoff potential prematurely during hard carbon sodiation, particularly at high current rates, which prevents the hard carbon anode from being fully sodiated.

BACKGROUND Poly(β-malic acid) (PMA) and pullulan are two valuable biopolymers that can be produced simultaneously by certain strains of pullulans. In previous studies, PMA production was successfully improved with reducing pullulan production. In the present study, a DO-shift control strategy was developed to obtain simultaneous high yields of PMA and pullulan. RESULTS PMA and pullulan co-production at various constant DO levels ranging from 10% to 90% saturation were carried out in a 5 L stirred tank fermentor. Based on the analysis of batch fermentation kinetics at various constant DO levels, a DO-shift control strategy that shifted the DO level from 30% saturation to 70% saturation at 72 h was developed to effectively obtain high productions of both PMA and pullulan. CONCLUSION By applying the DO-shift control strategy, the maximum concentrations of PMA and pullulan reached 118.6 g L−1 and 27.2 g L−1, respectively. PMA production was successfully improved without sacrificing pullulan production. © 2016 Society of Chemical Industry

The performance of redox-enhanced electrochemical capacitors (redox ECs) is substantially improved when oxidized catholyte (bromide) and reduced anolyte (viologen) are retained within the porous electrodes through reversible counterion-induced solid complexation. Investigation of the mechanism illustrates design principles and identifies pentyl viologen/bromide (PV/Br) as a new high-performance electrolyte. The symmetric PV/Br redox EC produces a specific energy of 48.5 W·h/kgdry at 0.5 A/gdry (0.44 kW/kgdry) with 99.7% Coulombic efficiency, maintains stability over 10 000 cycles, and functions identically when operated with reversed polarity.

According to the characteristics of the reflective optical microscope lighting system, an improved Kohler illumination system for the full-field optical coherence tomography system (FFOCT) was designed to realize the illumination of biological samples and living biological tissues. The illumination system differs from the conventional Kohler illumination system. The filament of the halogen lamp is imaged on the back focal plane of the microscope objective, then parallel light is incident on the sample plane. The improved Kohler illumination system uses a halogen lamp as the light source and is divided into two parts: the condenser front and rear groups. The front condenser group uses two double-glued structures, and the rear group uses a double-coupled lens. The optical design software Zemax was used to optimize the design, and the illumination analysis software Tracepro was used to trace the ray and simulate the imaging of the light source in the front focal plane of the microscope objective. The entire improved Kohler illumination optical path has a total length of 594 mm, the diaphragm is 122 mm from the front group of the condenser, 99 mm from the rear group, and the working distance is 292 mm; the luminous efficiency of the receiving surface is as high as 60.38%, and the edge of the light spot is smooth and clear. The illumination system makes full use of the optical power emitted by the light source and facilitates the placement of a device such as a splitting prism between the condenser and the microscope objective, which satisfies the requirement of the entire machine well.

Full-disc vector magnetograph (FMG) is one of the main loads in the Advanced Space-based Solar Observatory. FMG is used to realize scientific goals of observing full-disk vector magnetic field with center wavelength of 532.4 nm. The optical system of FMG consists of polarized optical system and imaging optical system, and the imaging optical system composes of the front window and telescope system. The front window has the capability for providing proper situation for scientific observation by absorbing high energy of solar irradiance coming from space while reflecting wavelength of non-scientific investigation beyond wavelength of 532.4±5 nm. The study analyzed the influence of complex space environment on optical glasses. As a result, the material of fused silica, while two pieces of flat glass parallel with 3mm separation structure and thickness of 15mm are determined. Finally, the results show that design for the front window meet the required specifications.

Table S1. Primers applied in qPCR. (DOCX 14 kb)

Figure S1. Validation for the regulatory effect of Circ-SMARCA5 on miR-767-5p. Description of data: The expression of miR-767-5p was decreased in SMARCA5 (+) group compared with Control(+) group and increased in SMARCA5(−) group compared with Control(−) group in NCI-H299 cells (A), U226 cells (B), OPM2 cells (C) and JJN3 cells (D). Comparisons of miR-767-5p expressions were performed using t test and P

Table S2. Antibodies applied in Western Blot. (DOCX 14 kb)

Pot experiment was performed to study the effect of garbage enzyme from the peel dregs of kiwifruit and Rosa roxburghii on the growth of castor and the contents of heavy metals (Cu, Zn, Cd and Pb) in the aerial part. The results indicated that the addition of two kinds of garbage enzyme with different concentrations was beneficial to the growth of castor, and the biomass of castor could be increased by up to 80%. High-concentration of Rosa roxburghii enzyme inhibited the absorption of heavy metals by castor, low-concentration of Rosa roxburghii enzyme showed a promotion effect; while high-concentration of kiwifruit enzyme increased the content of heavy metals in the aerial part of castor, low-concentration of kiwifruit enzyme showed inhibition, with a maximum decrease of 21% ∼ 42%. The results showed that kiwifruit enzyme with 1:800 diluted concentration could promote the growth of castor, and had the best inhibition effect on heavy metal absorption of castor.

We report a new electrochemical capacitor with an aqueous KI-KOH electrolyte that exhibits a higher specific energy and power than the state-of-the-art nonaqueous electrochemical capacitors. In addition to electrical double layer capacitance, redox reactions in this device contribute to charge storage at both positive and negative electrodes via a catholyte of IOx -/I- couple and a redox couple of H2O/Had on the negative electrode, respectively. Here, we, for the first time, report utilizing IOx -/I- redox couple for the positive electrode, which pins the positive electrode potential to be 0.4-0.5 V vs. Ag/AgCl. With the positive electrode potential pinned, we can polarize the cell to 1.6 V without breaking down the aqueous electrolyte so that the negative electrode potential could reach -1.1 V vs. Ag/AgCl in the basic electrolyte, greatly enhancing energy storage. Both mass spectrometry and Raman spectrometry confirm the formation of IO3 - ions (+5) from I- (-1) after charging. Based on the total mass of electrodes and electrolyte in a practically relevant cell configuration, the device exhibits a maximum specific energy of 7.1 Wh/kg, operates between -20 to 50 °C, provides a maximum specific power of 6222 W/kg, and has a stable cycling life with 93% retention of the peak specific energy after 14,000 cycles.

Current synthetic methods of biomass-derived activated carbon call for a costly chemical or physical activation process. Herein, we report a simple one-step annealing synthesis yielding a high surface area cellulose-derived activated carbon. We discover that simply varying the flow rate of Argon during pyrolysis enables ‘self-activation’ reactions that can tune the specific surface areas of the resulting carbon, ranging from 98 m2/g to values as high as 2600 m2/g. Furthermore, we, for the first time, observe a direct evolution of H2 from the pyrolysis, which gives strong evidence towards an in situ self-activation mechanism. Surprisingly, the obtained activated carbon is a crumbled graphene nanostructure composed of interconnected sheets, making it ideal for use in an electrochemical capacitor. The cellulose-derived nanoporous carbon exhibits a capacitance of 132 F g−1 at 1 A g−1, a performance comparable to the state-of-the-art activated carbons. This work presents a fundamentally new angle to look at the synthesis of activated carbon, and highlights the importance of a controlled inert gas flow rate during synthesis in general, as its contributions can have a very large impact on the final material properties.

A novel ambient hydrolysis deposition (AHD) methodology that employs sequential water adsorption followed by a hydrolysis reaction to infiltrate SnO2 nanoparticles into the nanopores of mesoporous carbon in a conformal and controllable manner is introduced. The empty space in the SnO2/C composites can be adjusted by varying the number of AHD cycles. An SnO2/C composite with an intermediate SnO2 loading exhibited an initial specific delithiation capacity of 1054 mAh g(-1) as an anode for Li-ion batteries. The capacity contribution from SnO2 in the composite electrode approaches the theoretical capacity of SnO2 (1494 mAh g(-1)) if both Sn alloying and SnO2 conversion reactions are considered to be reversible. The composite shows a specific capacity of 573 mAh g(-1) after 300 cycles, that is, one of the most stable cycling performances for SnO2/mesoporous carbon composites. The results demonstrated the importance of well-tuned empty space in nanostructured composites to accommodate expansion of the electrode active mass during alloying/dealloying and conversion reactions.

Structural characterization of the exopolysaccharide with FT-IR spectrum (a), 1H-NMR spectrum (b) and 13C-NMR spectrum (c). (DOCX 275Â kb)

Background poly(L-malic acid) (PMA) is a water-soluble polyester with many attractive properties in medicine and food industries, but the high cost of PMA fermentation has restricted its further application for large-scale production. To overcome this problem, PMA production from Jerusalem artichoke tubers was successfully performed. Additionally, a valuable exopolysaccharide, pullulan, was co-produced with PMA by Aureobasidum pullulans HA-4D. Results The Jerusalem artichoke medium for PMA and pullulan co-production contained only 100 g/L hydrolysate sugar, 30 g/L CaCO3 and 1 g/L NaNO3. Compared with the glucose medium, the Jerusalem artichoke medium resulted in a higher PMA concentration (114.4 g/L) and a lower pullulan concentration (14.3 g/L) in a 5 L bioreactor. Meanwhile, the activity of pyruvate carboxylase and malate dehydrogenas was significantly increased, while the activity of α-phosphoglucose mutase, UDP-glucose pyrophosphorylase and glucosyltransferase was not affected. To assay the economic-feasibility, large-scale production in a 1 t fermentor was performed, yielding 117.5 g/L PMA and 15.2 g/L pullulan. Conclusions In this study, an economical co-production system for PMA and pullulan from Jerusalem artichoke was developed. The medium for PMA and pullulan co-production was significantly simplified when Jerusalem artichoke tubers were used. With the simplified medium, PMA production was obviously stimulated, which would be associated with the improved activity of pyruvate carboxylase and malate dehydrogenas. Electronic supplementary material The online version of this article (doi:10.1186/s12896-017-0340-y) contains supplementary material, which is available to authorized users.

The bandgap in graphene-based materials can be tuned from 0 eV to that of benzene by changing size and/or surface chemistry, making it a rising carbonbased fl uorescent material. Here, the surface chemistry of small size graphene (graphene quantum dots, GQDs) is tuned programmably through modifi cation or reduction and green luminescent GQDs are changed to blue luminescent GQDs. Several tools are employed to characterize the composition and morphology of resultants. More importantly, using this system, the luminescence mechanism (the competition between both the defect state emission and intrinsic state emission) is explored in detail. Experiments demonstrate that the chemical structure changes during modifi cation or reduction suppresses non-radiative recombination of localized electron-hole pairs and/or enhances the integrity of surface π electron network. Therefore the intrinsic state emission plays a leading role, as opposed to defect state emission in GQDs. The results of time-resolved measurements are consistent with the suggested PL mechanism. Up-conversion PL of GQDs is successfully applied in near-IR excitation for bioimaging.

We report that crystalline 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA), an organic solid, is highly amenable to host divalent metal ions, i.e., Mg2+ and Ca2+, in aqueous electrolytes, where the van der Waals structure is intrinsically superior in hosting charge-dense ions. We observe that the divalency nature of Mg2+ causes never-reported unique squeezing deformation of the electrode structure, where it contracts and expands in different crystallographic directions when hosting inserted Mg-ions. This phenomenon is revealed experimentally by ex situ x-ray diffraction and transmission electron microscopy, and is investigated theoretically by first-principles calculations. Interestingly, hosting one Mg2+ ion requires the coordination from three PTCDA molecules in adjacent columns of stacked molecules, which rotates the columns, thus reducing the (011) spacing but increasing the (021) spacing. We demonstrate that a PTCDA Mg-ion electrode delivers a reversible capacity of 125 mA h g-1, which may include a minor contribution of hydronium storage, a good rate capability of retaining 75 mA h g-1 at 500 mA g-1 (or 3.7 C), and stable cycle life. We also report Ca2+ storage in PTCDA, where a reversible capacity of over 80 mA h g-1 is delivered.

Energy storage is the absent enabler to facilitate the proliferation of renewable-but-intermittent solar and wind energy. There is one primary metric for stationary storage: levelized energy cost over the life time of devices. It is, thus, a must to rely on earth-abundant elements, which rules out lithium-based devices for the grid-scale storage purposes as lithium is rare and its excavation is geopolitically challenged. This warrants attention for alternative rechargeable batteries. At Oregon State University, we seek fundamental understanding of design principles of electrodes for new sustainable batteries. We take an iterative approach to gain knowledge by integrating rational syntheses, advanced characterization, including synchrotron x-ray, neutron scattering, and associated pair distribution function studies, as well as DFT calculations. In this talk, I will talk about our recent results on the mechanisms of Na-ion and K-ion storage in non-graphithic carbon. I will introduce a design principle of hard carbon anode for Na-ion batteries based on its structure-property correlations. I will introduce limitations of carbon anode materials for K-ion storage and strategies in addressing them. I will discuss the relevance of organic solids as cathode of dual-ion batteries. Additionally, I will share new results on the emerging hydronium-ion batteries and ammonium-ion batteries.

Electrochemical double-layer capacitors exhibit high power and long cycle life but have low specific energy compared with batteries, limiting applications. Redox-enhanced capacitors increase specific energy by using redox-active electrolytes that are oxidized at the positive electrode and reduced at the negative electrode during charging. Here we report characteristics of several redox electrolytes to illustrate operational/self-discharge mechanisms and the design rules for high performance. We discover a methyl viologen (MV)/bromide electrolyte that delivers a high specific energy of ∼14 Wh kg−1 based on the mass of electrodes and electrolyte, without the use of an ion-selective membrane separator. Substituting heptyl viologen for MV increases stability, with no degradation over 20,000 cycles. Self-discharge is low, due to adsorption of the redox couples in the charged state to the activated carbon, and comparable to cells with inert electrolyte. An electrochemical model reproduces experiments and predicts that 30–50 Wh kg−1 is possible with optimization., The energy density of electrochemical capacitors can be increased by using a redox-active electrolyte, but such capacitors often suffer from significant self-discharge and low operating voltage. Here, the authors report a new redox-active aqueous electrolyte to effectively tackle the problems.