A sulfotransferase gene BnSOT-like1 has a minor genetic effect on seed glucosinolate content in Brassica napus

The theory and associated selection methods of classical quantitative genetics are based on the multifactorial or polygene hypothesis.Major genes or quantitative trait loci(QTL)in modern quantitative genetics based on a“major gene plus polygenes”genetic system have been paid much attention in genetic studies.However,it remains unclear how the numerous minor genes act,although the polygene theory has sustained genetic improvement in plants and animals for more than a hundred years.In the present study,we identified a novel minor gene,BnSOT-like1(BnaA09g53490D),which is a sulfotransferase(SOT)gene catalyzing the formation of the core glucosinolate(GSL)structure in Brassica napus.This gene has been occasionally found during investigations of plant height-related genes,but has not been identified by QTL mapping because of its small phenotypic effects on GSL content.The overexpression of BnSOT-like1 up-regulated the expression of aliphatic GSL-associated genes,leading to a high seed aliphatic GSL content,and the overexpression of the allelic gene Bnsot-like1 did not increase seed GSL content.These findings suggest that the SOT gene has a marked effect on a quantitative trait from a reverse genetics standpoint,but a minor effect on the quantitative trait in its natural biological state.Because of the redundancy of GSL biosynthetic genes in the allotetraploid species B.napus,mutations of a single functional gene in the pathway will not result in significant phenotypic changes,and that the genes in biosynthetic pathways such as BnSOT-like1 in our study have minor effects and may be called polygenes in contrast to the reported three regulatory genes(BnHAG1s)which strongly affect GSL content in B.napus.The present study has shed light on a minor gene for a quantitative trait.

All-fiber erbium-doped dissipative soliton laser with multimode interference based on saturable-reserve saturable hybrid optical switch

Reverse saturable absorption is essential for the realization of dissipative solitons.In this paper,we introduce reverse saturable absorption by using nonlinear multimode interference(NL-MMI),for the first time,to the best of our knowledge,and obtain a stable dissipative soliton operation.By adjusting the coupling efficiency from multimode fiber to single mode fiber,the absorption properties of NL-MMI can be switched between saturation and reverse saturation.The dissipative soliton can be obtained with pulse width of 975 fs in the experiment,the 3-dB bandwidth at 1555 nm is 16 nm,and the maximum output power is 11.48 m W.The nonlinear absorption optical modulation and high damage threshold characteristics of the NL-MMI based ultrafast optical switch provide a new idea for realizing dissipative solitons.

Probing the structure of multi-center molecules with odd–even high harmonics

We study high-order harmonic generation(HHG)from multi-center asymmetric linear molecules numerically and analytically.Our simulations show that odd and even HHG spectra of the asymmetric multi-center system respond differently to the change of the molecular structure.Specifically,when the internuclear distances between these nuclei of the molecule have a small change,the odd spectra usually do not change basically,but the even spectra differ remarkably.Based on this phenomenon,a simple procedure is proposed to probe the positions of these nuclei with odd–even HHG.Our results shed light on attosecond probing of the structure of multi-center molecules using HHG.

Multiple bottle beams based on metasurface optical field modulation and their capture of multiple atoms

Compared to conventional devices, metasurfaces offer the advantages of being lightweight, with planarization and tuning flexibility. This provides a new way to integrate and miniaturize optical systems. In this paper, a metasurface capable of generating multiple bottle beams was designed. Based on the Pancharatnam–Berry(P–B) phase principle, the metasurface lens can accurately control the wavefront by adjusting the aspect ratio of the titanium dioxide nanopillars and the rotation angle. When irradiated by left-handed circularly polarized light with a wavelength of 632.8 nm, the optical system can produce multiple micron bottle beams. Taking two bottle beams as examples, the longitudinal full widths at half-maximum of the optical tweezers can reach 0.85 μm and 1.12 μm, respectively, and the transverse full widths at half-maximum can reach 0.46 μm and 0.6 μm. Also, the number of generated bottle beams can be varied by controlling the size of the annular obstacle. By changing the x-component of the unit rotation angle, the metasurface can also change the shape of the bottle beam - the beam cross-section can be changed from circular to elliptical. This paper also analyzes the trapping of ytterbium atoms by the multi bottle beam acting as optical tweezers. It is found that the multi bottle beam can cool and trap multiple ytterbium atoms.

Recent advances in multimodal sensing integration and decoupling strategies for tactile perception

Human skin perceives external environmental stimulus by the synergies between the subcutaneous tactile corpuscles.Soft electronics with multiple sensing capabilities by mimicking the function of human skin are of significance in health monitoring and artificial sensation.The last decade has witnessed unprecedented development and convergence between multimodal tactile sensing devices and soft bioelectronics.Despite these advances,traditional flexible electronics achieve multimodal tactile sensing for pressure,strain,temperature,and humidity by integrating monomodal sensing devices together.This strategy results in high energy consumption,limited integration,and complex manufacturing process.Various multimodal sensors and crosstalk-free sensing mechanisms have been proposed to bridge the gap between natural sensory system and artificial perceptual system.In this review,we provide a comprehensive summary of tactile sensing mechanism,integration design principles,signal-decoupling strategies,and current applications for multimodal tactile perception.Finally,we highlight the current challenges and present the future perspectives to promote the development of multimodal tactile perception.

Single-phase La_(0.8)Sr_(0.2)Co_(1-x)Mn_(x)O_(3-δ) electrocatalyst as a triple H^(+)/O^(2-)/e^(-) conductor enabling high-performance intermediate-temperature water electrolysis

Hydrogen,especially the“green hydrogen”based on water electrolysis,is of great importance to build a sustainable society due to its high-energy-density,zero-carbon-emission features,and wide-range applications.Today's water electrolysis is usually carried out in either low-temperature(<100℃),e.g.,alkaline electrolyzer,or high-temperature(>700℃)applications,e.g.,solid oxide electrolyzer.However,the low-temperature devices usually suffer from high applied voltages(usually>1.5 V@0.01 A cm^(-2))and high cost;meanwhile,the high-temperature ones have an unsatisfied lifetime partially due to the incompatibility among components.Reasonably,an intermediate-temperature device,namely,proton ceramic cell(PCC),has been recently proposed.The widely-used air electrode for PCC is based on double O^(2-)/e^(-)conductor or composited O^(2-)/e^(-)-H^(+)conductor,limiting the accessible reaction region.Herein,we designed a single-phase La_(0.8)Sr_(0.2)Co_(1-x)Mn_(x)O_(3-δ)(LSCM)with triple H^(+)/O^(2-)/e^(-)conductivity as the air electrode for PCCs.Specifically,the La_(0.8)Sr_(0.2)Co_(0.8)Mn_(0.2)O_(3-δ)(LSCM8282)incorporates 5.8%proton carriers in molar fraction at 400℃,indicating superior proton conducting ability.Impressively,a high current density of 1580 mA cm^(-2) for hydrogen production(water electrolysis)is achieved at 1.3 V and 650℃,surpassing most low-and high-temperature devices reported so far.Meanwhile,such a PCC can also be operated under a reversible fuel cell mode,with a peak power density of 521 mW cm^(-2) at 650℃.By correlating the electrochemical performances with the hydrated proton concentration of single-phase triple conducting air electrodes in this work and our previous work,a principle for rational design of high-performance PCCs is proposed.

Multifunctional high-performance pressure/proximity/temperature sensors enabled by hybrid resistive-supercapacitive response

The issue of sensitivity attenuation in high-pressure region has been a persistent concern for pressure-sensitive electronic skins.In order to tackle such trade-off between sensitivity and linear range,herein,a hybrid piezoresistive-supercapacitive(HRSC)strategy is proposed via introducing a piezoresistive porous aerogel layer between the charge collecting electrodes and iontronic films of the pressure sensors.Surprisingly,the HRSC-induced impedance regulation and supercapacitive behavior contribute to significant mitigation in sensitivity attenuation,achieving high sensitivity across wide linear range(44.58 kPa^(−1)from 0 to 3 kPa and 23.6 kPa^(−1)from 3 to 12 kPa).The HRSC pressure sensor exhibits a low detection limit of 1 Pa,fast responsiveness(~130 ms),and excellent cycling stability,allowing to detect tiny pressure of air flow,finger bending,and human respiration.Meanwhile,the HRSC sensor exhibits exceptional perception capabilities for proximity and temperature,broadening its application scenarios in prosthetic perception and electronic skin.The proposed HRSC strategy may boost the ongoing research on structural design of high-performance and multimodal electronic sensors.

Optimization of fermentation medium for xylanase-producing strain Xw2

To improve the fermentation yield of xylanase by optimizing the fermentation conditions for strain Xw2, a Plackett-Burman design was used to evaluate the effects of eight variables on xylanase production by strain Xw2. The steepest ascent （descent） method was used to approach the optimal response surface experimental area. The optimal fermentation conditions were obtained by central composite design and response surface analysis. The results showed that the composition of the optimal fermentation medium was corn cob ＋ 1.5% wheat bran （1：1）, 0.04% MnSO4, 0.04% K2HPO4. 3H2O, and an inoculum size of 6% in 50 mL liquid volume （pH = 6.0）. The optimal culture conditions were 28oc at 150 r/min for 54.23 h. The results of this study can serve as the basis for the industrial production and application of xylanase.