Dissipationless gyrotropic magnetic Hall effect

A dissipationless longitudinal current can be generated by a pure magnetic field through the chiral magnetic effect. Herein, we propose that a pure oscillating magnetic field through Zeeman coupling can further drive an AC magnetic Hall current in two-dimensional systems without inversion symmetry. We dub this effect the "gyrotropic magnetic Hall effect" (GMHE), in analogy with the gyrotropic current achieved by rectifying the optical fields. Importantly, we find that the GMHE conductivity is a reactive or dissipationless transport coefficient, which is even under time-reversal symmetry. We reveal the "Zeeman Berry curvature" as the quantum origin of the GMHE, whose integral over all states below the Fermi energy gives the GMHE conductivity. Furthermore, by symmetry analysis, we show that the GMHE can appear in a wide range of two-dimensional materials. To demonstrate our proposal, we evaluate the GMHE current in two-dimensional Rashba system and in the surface of topological insulator, where a low-frequency magnetic field with a small amplitude can be converted into a detectable Hall voltage

Transparent hydrogel with enhanced water retention capacity by introducing highly hydratable salt

Polyacrylamide hydrogels containing salt as electrolyte have been used as highly stretchable transparent electrodes in flexible electronics, but those hydrogels are easy to dry out due to water evaporation. Targeted, we try to enhance water retention capacity of polyacrylamide hydrogel by introducing highly hydratable salts into the hydrogel. These hydrogels show enhanced water retention capacity in different level. Specially, polyacrylamide hydrogel containing high content of lithium chloride can retain over 70% of its initial water even in environment with relative humidity of only 10% RH. The excellent water retention capacities of these hydrogels will make more applications of hydrogels become possible.Engineering and Applied Science

Harnessing the Power of David against Goliath: Exploring Instruction Data Generation without Using Closed-Source Models

Instruction tuning is instrumental in enabling Large Language Models~(LLMs) to follow user instructions to complete various open-domain tasks. The success of instruction tuning depends on the availability of high-quality instruction data. Owing to the exorbitant cost and substandard quality of human annotation, recent works have been deeply engaged in the exploration of the utilization of powerful closed-source models to generate instruction data automatically. However, these methods carry potential risks arising from the usage requirements of powerful closed-source models, which strictly forbid the utilization of their outputs to develop machine learning models. To deal with this problem, in this work, we explore alternative approaches to generate high-quality instruction data that do not rely on closed-source models. Our exploration includes an investigation of various existing instruction generation methods, culminating in the integration of the most efficient variant with two novel strategies to enhance the quality further. Evaluation results from two benchmarks and the GPT-4 model demonstrate the effectiveness of our generated instruction data, which can outperform Alpaca, a method reliant on closed-source models. We hope that more progress can be achieved in generating high-quality instruction data without using closed-source models

Cyclic performance of viscoelastic dielectric elastomers with solid hydrogel electrodes

Hydrogels containing electrolyte can work as ionic conductors to actuate dielectric elastomer (DE) artificial muscles. Based on a popular design of a circular actuator, we study theoretically and experimentally the cyclic performance of acrylic DE actuators with solid hydrogel electrodes. The viscoelasticity of solid electrodes constrains the maximum strain that is attainable for one cycle of triangular voltage, and it also diminishes the accumulated increment of the maximum strain after many cycles of loadings.Engineering and Applied Science

Stretchable and transparent hydrogels as soft conductors for dielectric elastomer actuators

A soft ionic conductor can serve as an artificial nerve in an artificial muscle. A polyacrylamide hydrogel is synthesized containing a hygroscopic salt, lithium chloride. Two layers of the hydrogel are used as ionic conductors to sandwich a dielectric elastomer and fabricate a highly stretchable and transparent actuator. When the two layers of the hydrogels are subject to a voltage, the actuator reduces its thickness and expands. An areal strain of 134% is demonstrated. The voltage-strain curves are calculated by using a model that accounts for the elastic constraint of the hydrogel and the inhomogeneous deformation of the actuator. For actuators fabricated with the hydrogel of various thicknesses and with the dielectric elastomer of various prestretches, excellent agreements are found between experimental data and theoretical predictions.Engineering and Applied Science

Characterization of Sucrose transporter alleles and their association with seed yield-related traits in Brassica napus L

<p>Abstract</p> <p>Background</p> <p>Sucrose is the primary photosynthesis product and the principal translocating form within higher plants. <it>Sucrose transporters </it>(<it>SUC/SUT</it>) play a critical role in phloem loading and unloading. Photoassimilate transport is a major limiting factor for seed yield. Our previous research demonstrated that <it>SUT </it>co-localizes with yield-related quantitative trait loci. This paper reports the isolation of <it>BnA7.SUT1 </it>alleles and their promoters and their association with yield-related traits.</p> <p>Results</p> <p>Two novel <it>BnA7.SUT1 </it>genes were isolated from <it>B. napus </it>lines 'Eagle' and 'S-1300' and designated as <it>BnA7.SUT1.a </it>and <it>BnA7.SUT1.b</it>, respectively. The BnA7.SUT1 protein exhibited typical SUT features and showed high amino acid homology with related species. Promoters of <it>BnA7.SUT1.a </it>and <it>BnA7.SUT1.b </it>were also isolated and classified as <it>pBnA7.SUT1.a </it>and <it>pBnA7.SUT1.b</it>, respectively. Four dominant sequence-characterized amplified region markers were developed to distinguish <it>BnA7.SUT1.a </it>and <it>BnA7.SUT1.b</it>. The two genes were estimated as alleles with two segregating populations (F₂and BC₁) obtained by crossing '3715'×'3769'. <it>BnA7.SUT1 </it>was mapped to the A7 linkage group of the TN doubled haploid population. <it>In silico </it>analysis of 55 segmental <it>BnA7.SUT1 </it>alleles resulted three <it>BnA7.SUT1 </it>clusters: <it>pBnA7.SUT1.a- BnA7.SUT1.a </it>(type I), <it>pBnA7.SUT1.b- BnA7.SUT1.a </it>(type II), and <it>pBnA7.SUT1.b- BnA7.SUT1.b </it>(type III). Association analysis with a diverse panel of 55 rapeseed lines identified single nucleotide polymorphisms (SNPs) in promoter and coding domain sequences of <it>BnA7.SUT1 </it>that were significantly associated with one of three yield-related traits: number of effective first branches (EFB), siliques per plant (SP), and seed weight (n = 1000) (TSW) across all four environments examined. SNPs at other <it>BnA7.SUT1 </it>sites were also significantly associated with at least one of six yield-related traits: EFB, SP, number of seeds per silique, seed yield per plant, block yield, and TSW. Expression levels varied over various tissue/organs at the seed-filling stage, and <it>BnA7.SUT1 </it>expression positively correlated with EFB and TSW.</p> <p>Conclusions</p> <p>Sequence, mapping, association, and expression analyses collectively showed significant diversity between the two <it>BnA7.SUT1 </it>alleles, which control some of the phenotypic variation for branch number and seed weight in <it>B. napus </it>consistent with expression levels. The associations between allelic variation and yield-related traits may facilitate selection of better genotypes in breeding.</p

A Major and Stable QTL for Bacterial Wilt Resistance on Chromosome B02 Identified Using a High-Density SNP-Based Genetic Linkage Map in Cultivated Peanut Yuanza 9102 Derived Population

Bacterial wilt (BW) is one of the important diseases limiting the production of peanut (Arachis hypogaea L.) worldwide. The sufficient precise information on the quantitative trait loci (QTL) for BW resistance is essential for facilitating gene mining and applying in molecular breeding. Cultivar Yuanza 9102 is BW resistant, bred from wide cross between cultivated peanut Baisha 1016 and a wild diploid peanut species A. chacoense with BW resistance. In this study, we aim to map the major QTLs related to BW-resistance in Yuanza 9102. A high density SNP-based genetic linkage map was constructed through double-digest restriction-site-associated DNA sequencing (ddRADseq) technique based on Yuanza 9102 derived recombinant inbred lines (RILs) population. The map contained 2,187 SNP markers distributed on 20 linkage groups (LGs) spanning 1566.10 cM, and showed good synteny with AA genome from A. duranensis and BB genome from A. ipaensis. Phenotypic frequencies of BW resistance among RIL population showed two-peak distribution in four environments. Four QTLs explaining 5.49 to 23.22% phenotypic variance were identified to be all located on chromosome B02. The major QTL, qBWB02.1 (12.17–23.33% phenotypic variation explained), was detected in three environments showing consistent and stable expression. Furthermore, there was positive additive effect among these major and minor QTLs. The major QTL region was mapped to a region covering 2.3 Mb of the pseudomolecule B02 of A. ipaensis which resides in 21 nucleotide-binding site -leucine-rich repeat (NBS-LRR) encoding genes. The result of the major stable QTL (qBWB02.1) not only offers good foundation for discovery of BW resistant gene but also provide opportunity for deployment of the QTL in marker-assisted breeding in peanut

A male sterility-associated cytotoxic protein ORF288 in Brassica juncea causes aborted pollen development

Cytoplasmic male sterility (CMS) is a widespread phenomenon in higher plants, and several studies have established that this maternally inherited defect is often associated with a mitochondrial mutant. Approximately 10 chimeric genes have been identified as being associated with corresponding CMS systems in the family Brassicaceae, but there is little direct evidence that these genes cause male sterility. In this study, a novel chimeric gene (named orf288) was found to be located downstream of the atp6 gene and co-transcribed with this gene in the hau CMS sterile line. Western blotting analysis showed that this predicted open reading frame (ORF) was translated in the mitochondria of male-sterile plants. Furthermore, the growth of Escherichia coli was significantly repressed in the presence of ORF288, which indicated that this protein is toxic to the E. coli host cells. To confirm further the function of orf288 in male sterility, the gene was fused to a mitochondrial-targeting pre-sequence under the control of the Arabidopsis APETALA3 promoter and introduced into Arabidopsis thaliana. Almost 80% of transgenic plants with orf288 failed to develop anthers. It was also found that the independent expression of orf288 caused male sterility in transgenic plants, even without the transit pre-sequence. Furthermore, transient expression of orf288 and green fluorescent protein (GFP) as a fused protein in A. thaliana protoplasts showed that ORF288 was able to anchor to mitochondria even without the external mitochondrial-targeting peptide. These observations provide important evidence that orf288 is responsible for the male sterility of hau CMS in Brassica juncea

Nonprobabilistic reliability oriented topological optimization for multi-material heat-transfer structures with interval uncertainties

This study presents a nonprobabilistic reliability-based topology optimization (NRBTO) framework that combines a multi-material interpolation model and interval mathematics to achieve an optimal layout design for heat-transfer structures under unknown but bounded (UBB) uncertainties. In terms of the uncertainty quantification (UQ) issue, the interval dimension-wise method (IDWM) based on set collocation theory is first proposed to effectively determine the bounds of nodal temperature responses. For safety reasons, the interval reliability (IR) index corresponding to the thermal constraint is defined, and then a new design policy, i.e., the strategy of nonprobabilistic reliability oriented topological optimization is established. To circumvent problems of large-scale variable updating in a multi-material topology optimization procedure, theoretical deductions of the design sensitivity analysis are further given based on the adjoint-vector criterion and the chain principle. The validity and feasibility of the developed methodology are eventually demonstrated by several application examples