Redox state and metabolic responses to severe heat stress in lenok Brachymystax lenok (Salmonidae)

In order to provide new insights into the physiological responses of lenok (Brachymystax lenok: Salmonidae) to acute and severe heat stress (25°C, 48 h), dynamic changes in redox state and metabolic responses are studied combined biochemical index and non-targeted metabolome. Nicotinamide adenine dinucleotide (NAD+) consumption causes significant increases in ratio of reduced NADH to NAD+ and ratio of reduced nicotinamide adenine dinucleotide phosphate (NADPH) to NADP+, which induced the redox imbalance in heat stressed lenok. Lowered reduced glutathione/oxidized glutathione (GSH/GSSG) ratios suggested that more oxidized conditions occurred in heat-stressed lenok, leading to membrane lipid oxidation. The first few hours of heat stress promoted the activity of enzymes involved in anaerobic glycolysis (hexokinase, pyruvate kinase, lactic dehydrogenase) and glutamicpyruvic transaminase and glutamic oxaloacetic transaminase, which might lead to consumption of many carbohydrates and amino acid catabolism. These enzyme activities decreased with time in a possible compensatory strategy to manage anabolic and catabolic metabolism, maintaining the redox homeostasis. After 48 h of recovery, NAD+, carbohydrate levels and enzyme activities had returned to control levels, whereas many amino acids were consumed for repair and new synthesis. GSH remained at levels lower than controls, and the more oxidized conditions had not recovered, aggravating oxidative damage. Glutamic acid, glutamine, lysine and arginine may play important roles in survival of heat-stressed lenok

Tunable templating of photonic microparticles via liquid crystal order-guided adsorption of amphiphilic polymers in emulsions.

peer reviewedMultiple emulsions are usually stabilized by amphiphilic molecules that combine the chemical characteristics of the different phases in contact. When one phase is a liquid crystal (LC), the choice of stabilizer also determines its configuration, but conventional wisdom assumes that the orientational order of the LC has no impact on the stabilizer. Here we show that, for the case of amphiphilic polymer stabilizers, this impact can be considerable. The mode of interaction between stabilizer and LC changes if the latter is heated close to its isotropic state, initiating a feedback loop that reverberates on the LC in form of a complete structural rearrangement. We utilize this phenomenon to dynamically tune the configuration of cholesteric LC shells from one with radial helix and spherically symmetric Bragg diffraction to a focal conic domain configuration with highly complex optics. Moreover, we template photonic microparticles from the LC shells by photopolymerizing them into solids, retaining any selected LC-derived structure. Our study places LC emulsions in a new light, calling for a reevaluation of the behavior of stabilizer molecules in contact with long-range ordered phases, while also enabling highly interesting photonic elements with application opportunities across vast fields.R-AGR-3799 - C20/MS/14771094/ECLIPSE - LAGERWALL JanU-AGR-7141 - C21/MS/16325006/BIOFLICS - LAGERWALL Ja

Tunable templating of photonic microparticles via liquid crystal order-guided adsorption of amphiphilic polymers in emulsions

Multiple emulsions are usually stabilized by amphiphilic molecules that combine the chemical characteristics of the different phases in contact. When one phase is a liquid crystal (LC), the choice of stabilizer also determines its configuration, but conventional wisdom assumes that the orientational order of the LC has no impact on the stabilizer. Here we show that, for the case of amphiphilic polymer stabilizers, this impact can be considerable. The mode of interaction between stabilizer and LC changes if the latter is heated close to its isotropic state, initiating a feedback loop that reverberates on the LC in form of a complete structural rearrangement. We utilize this phenomenon to dynamically tune the configuration of cholesteric LC shells from one with radial helix and spherically symmetric Bragg diffraction to a focal conic domain configuration with highly complex optics. Moreover, we template photonic microparticles from the LC shells by photopolymerizing them into solids, retaining any selected LC-derived structure. Our study places LC emulsions in a new light, calling for a reevaluation of the behavior of stabilizer molecules in contact with long-range ordered phases, while also enabling highly interesting photonic elements with application opportunities across vast fields

Highly Active and Stable Fe-N-C Oxygen Reduction Electrocatalysts Derived from Electrospinning and In Situ Pyrolysis

Abstract High-performance electrocatalysts for the oxygen reduction reaction (ORR) are essential in electrochemical energy storage and conversion technologies. Fe-N-C electrocatalysts have been developed as one of the most promising alternatives to precious metal materials. Current M-N-C electrocatalysts usually are derived from high-temperature thermal treatment of a nitrogen-containing polymer or metal–organic frameworks (MOFs). Here, we developed Fe-N-C mesoporous nanofibers with low-cost urea and FeCl3 as the nitride and iron source; the electrocatalysts with abundant Fe-Nx active sites and large surface area were synthesized via electrospinning, in situ pyrolysis, and acid treatment process. The use of sealing conditions in the calcination process can effectively improve the nitrogen species content in the catalyst, which is important for improving performance. The as-prepared electrocatalyst material manifests well electrocatalytic performance for ORR in alkaline electrolyte (onset potential of 0.93 V and half-wave potential of 0.82 V); meanwhile, the electrocatalyst expresses good stability and methanol tolerance. This work may provide new thought for developing high-performance ORR electrocatalysts

A Differential Phase-Modulated Interferometer with Rotational Error Compensation for Precision Displacement Measurement

In this paper, a differential phase-modulated interferometer (DPMI) is proposed to compensate for the rotational error for precision displacement measurement. In DPMI, a reference interferometer sharing the same reference arm with the measurement interferometer is constructed. Using the two interferometers to differentially measure the displacement, the unbalanced environmental disturbance on the measurement can be minimized. An integrated 2 × 2 array photodetector (APD) is adopted in DPMI. Based on APD with differential wavefront sensing (DWS) technology, the rotation angle can be detected and compensated. Therefore, precision displacement without rotational error and unbalanced environmental disturbance can be achieved. Three confirmatory experiments were performed, and the experimental results show that the maximum displacement drift is reduced from 902.9 nm to 16.3 nm in 100 min stability test, the standard deviations between the pitch and yaw angles obtained by DPMI and Renishaw interferometer are 1.68 × 10−5° and 1.86 × 10−5°, respectively, and the maximum deviation between the measurement result of DPMI and the stage positioning before and after angle compensation is reduced from 5.207 μm to about 0.719 μm

Additional file 1: of Highly Active and Stable Fe-N-C Oxygen Reduction Electrocatalysts Derived from Electrospinning and In Situ Pyrolysis

Figure S1. EDX specter of FN-800 and the insert was the element ratio of C, N and Fe, respectively. Figure S2. Pore size distributions for FN-800. Figure S3. N2 absorption and desorptionof FN-800 without acid treat. Figure S4. XPS survey scan and N1 s high resolution spectra of FN-800 which uncover during carbonization process. Figure S5. Polarization curves at various speeds and a scan rate of 5 mV/s: (a) N-800; (b) F-800; K-L plots (J− 1 vs. ω-1/2) at different potentials of N-800 (c) and F-800 (d). Figure S6. LSV of the Fe-N-doped carbon nanofibers catalysts with different carbonize temperature in the range of 600–1000 °C. Table S1. Comparison of the ORR performance between FN-800 and other reported catalysts in 0.1 M KOH electrolyte. (PDF 843 kb

Preparation and Characterization of Mo Doped in BiVO4 with Enhanced Photocatalytic Properties

Molybdenum (Mo) doped BiVO4 was fabricated via a simple electrospun method. Morphology, structure, chemical states and optical properties of the obtained catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), N2 adsorption–desorption isotherms (BET) and photoluminescence spectrum (PL), respectively. The photocatalytic properties indicate that doping Mo into BiVO4 can enhance the photocatalytic activity and dark adsorption ability. The photocatalytic test suggests that the 1% Mo-BiVO4 shows the best photocatalytic activity, which is about three times higher than pure BiVO4. Meanwhile, 3% Mo-BiVO4 shows stronger dark adsorption than pure BiVO4 and 1% Mo-BiVO4. The enhancement in photocatalytic property should be ascribed to that BiVO4 with small amount of Mo doping could efficiently separate the photogenerated carries and improve the electronic conductivity. The high concentration doping would lead the crystal structure transformation from monoclinic to tetragonal phase, as well as the formation of MoO3 nanoparticles on the BiVO4 surface, which could also act as recombination centers to decrease the photocatalytic activity

Tunable templating of photonic microparticles via liquid crystal order-guided adsorption of amphiphilic polymers in emulsions

Abstract Multiple emulsions are usually stabilized by amphiphilic molecules that combine the chemical characteristics of the different phases in contact. When one phase is a liquid crystal (LC), the choice of stabilizer also determines its configuration, but conventional wisdom assumes that the orientational order of the LC has no impact on the stabilizer. Here we show that, for the case of amphiphilic polymer stabilizers, this impact can be considerable. The mode of interaction between stabilizer and LC changes if the latter is heated close to its isotropic state, initiating a feedback loop that reverberates on the LC in form of a complete structural rearrangement. We utilize this phenomenon to dynamically tune the configuration of cholesteric LC shells from one with radial helix and spherically symmetric Bragg diffraction to a focal conic domain configuration with highly complex optics. Moreover, we template photonic microparticles from the LC shells by photopolymerizing them into solids, retaining any selected LC-derived structure. Our study places LC emulsions in a new light, calling for a reevaluation of the behavior of stabilizer molecules in contact with long-range ordered phases, while also enabling highly interesting photonic elements with application opportunities across vast fields