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Four LMW-m and one novel chimeric (between LMW-i and LMW-m types) low-molecular-weight glutenin subunit (LMW-GS) genes from Aegilops neglecta (UUMM), Ae. kotschyi (UUSS), and Ae. juvenalis (DDMMUU) were isolated and characterized. Sequence structures showed that the 4 LMW-m-type genes, assigned to the M genome of Ae. neglecta, displayed a high homology with those from hexaploid common wheat. The novel chimeric gene, designed as AjkLMW-i, was isolated from both Ae. kotschyi and Ae. juvenalis and shown to be located on the U genome. Phylogentic analysis demonstrated that it had higher identity to the LMW-m-type than the LMW-i-type genes. A total of 20 single nucleotide polymorphisms (SNPs) were detected among the 4 LMW-m genes, with 13 of these being nonsynonymous SNPs that resulted in amino acid substitutions in the deduced mature proteins. Phylogenetic analysis demonstrated that it had higher identity to the LMW-m-type than the LMW-i-type genes. The divergence time estimation showed that the M and D genomes were closely related and diverged at 5.42 million years ago (MYA) while the differentiation between the U and A genomes was 6.82 MYA. We propose that, in addition to homologous recombination, an illegitimate recombination event on the U genome may have occurred 6.38 MYA and resulted in the generation of the chimeric gene AjkLMW-i, which may be an important genetic mechanism for the origin and evolution of LMW-GS Glu-3 alleles as well as other prolamin genes.

A working memory selection task combining directed-forgetting and memory-scanning paradigms was used to test the hypothesis that difficulty in selecting target from distractor items in working memory depends on the competition between target and distractor representations, as is commonly assumed in perceptual selection research. Participants memorized two trigrams and were then cued to select one as the new memory set and forget the other. They later saw a test letter and made judgment as to whether the letter was in the selected trigram, i.e., the new memory set. Selection difficulty was examined by manipulating the type of selection cues and the time the cue could be utilized. While re-presenting the targets in the cue display facilitated selection, re-presenting distractors did not impede selection. The results suggest that working memory selection may depend more on the activation from representations of the target than of the distractor.

Two new x-type high-molecular-weight glutenin subunits with similar size to 1Dx5, designated [1Dx5.sup.*t] and [1Dx5.1.sup.*t] in Aegilops tauschii, were identified by SDS-PAGE, RP-HPLC, and MALDI-TOF-MS. The coding sequences were isolated by AS-PCR and the complete ORFs were obtained. Allele [1Dx5.sup.*t] consists of 2481 bp encoding a mature protein of 827 residues with deduced [M.sub.r] of 85,782 Da whereas [1Dx5.1.sup.*t] comprises 2526 bp encoding 842 residues with [M.sub.r] of 87,663 Da. The deduced [M.sub.r]'s of both genes were consistent with those determined by MALDI-TOF-MS. Molecular structure analysis showed that the repeat motifs of [1Dx5.sup.*t] were correspondingly closer to the consensus compared to [1Dx5.1.sup.*t] and 1Dx5 subunits. A total of 11 SNPs (3 in [1Dx5.sup.*t] and 8 in [1Dx5.1.sup.*t]) and two indels in [1Dx5.sup.*t] were identified, among which 8 SNPs were due to C-T or A-G transitions (an average of 73%). Expression of the cloned ORFs and N-terminal sequencing confirmed the authenticities of the two genes. Interestingly, several hybrid clones of [1Dx5.sup.*t] expressed a slightly smaller protein relative to the authentic subunit present in seed proteins; this was confirmed to result from a deletion of 180 bp through illegitimate recombination as well as an in-frame stop codon. Network analysis demonstrated that [1Dx5.sup.*t], [1Dx2.sup.t], [1Dx1.6.sup.t], and [1Dx2.2.sup.*] represent a root within a network and correspond to the common ancestors of the other Glu-D-l-1 alleles in an associated star-like phylogeny, suggesting that there were at least four independent origins of hexaploid wheat. In addition to unequal homologous recombination, duplication and deletion of large fragments occurring in Glu-D-1-1 alleles were attributed to illegitimate recombination.

Abstract: A novel y-type high molecular mass glutenin subunit (HMM-GS) possessing a mobility that is slightly slower than that of the subunit Dy10 obtained by SDS-PAGE, named [Dy10.1.sup.t], in the [...]

BACKGROUND: 10‐Hydroxy‐cis‐12‐octadecenoic acid (10‐HOE, 10‐OH C18:1), an emerging functional fatty acid, has anti‐fungal and anti‐inflammatory effects. 10‐HOE is synthesized by bacterial 10‐linoleic acid hydratase (10‐LHT) with linoleic acid as the substate. However, the characterization of 10‐LHT and its targeted synthesis of 10‐HOE have been rarely reported. In this study, the recombinant 10‐LHT from Lactiplantibacillus plantarum ZS2058 was characterized, and the biocatalysis of 10‐HOE using crude enzyme was optimized. RESULTS: The recombinant 10‐LHT catalyzed the conversion of linoleic acid (C18:2) to 10‐HOE as identified using gas chromatography‐mass spectrometry (GC–MS). It showed a molecular weight of about 70 kDa on sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS‐PAGE), and was a flavin adenine dinucleotide (FAD)‐dependent enzyme. The activity of 10‐LHT was optimal at pH 6.5 and 25 °C, and it was pH‐stable but thermo‐sensitive. The optimal condition for the 10‐HOE biosynthesis using crude enzyme was 5 g L−1 linoleic acid (C18:2), 148.0 U mL−1 10‐LHT, 0.05 mmol L−1 FAD, 2% methanol and 100 mmol L−1 sodium chloride at 25 °C and pH 6.5. A conversion yield of 47.8 ± 1.5% and the corresponding 10‐HOE concentration of 2.4 ± 0.1 g L−1 were achieved at 48 h under the optimal reaction conditions. CONCLUSION: This work achieved the highest conversion yield of 10‐HOE with the highest substrate concentration, and provides some useful information for the industrial production of 10‐HOE. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this paper, by using the special structure of the real representation of quaternion matrices, the properties of the Moore–Penrose inverse of quaternion matrices and the Kronecker product of matrices, we study least-squares bihermitian and skew bihermitian solutions of the quaternion matrix equation AXB = C, respectively. First we study the special structures of quaternion bihermitian and skew bihermitian matrices. Then the problem of solving the least-squares bihermitian and skew bihermitian solutions of the quaternion matrix equation AXB = C can be transformed into particular real linear system using these special structures. We deduce the form of all least-squares bihermitian and skew bihermitian solutions of the quaternion matrix equation AXB = C and propose real structure-preserving algorithms to compute the minimal norm least-squares bihermitian and skew bihermitian solution. All the computation process only involve real arithmetic. Numerical examples are provided to verify the effectiveness of our algorithms. Particularly, we also propose the conditions and computation method of bihermitian and skew bihermitian solutions of quaternion matrix equation AXB = C. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the retinal vessel oxygen saturation in patients with internal carotid artery stenosis (ICAS). Methods: This is a cross‐sectional study. Sixteen patients with unilateral moderate or worse ICAS (≥50%) and no fundus diseases were included in the study. Sixteen gender‐ and age‐matched healthy subjects were selected as controls. The mean oxygen saturation and vessel diameters of the retinal arterioles and venules were obtained using a dual‐wavelength spectrophotometric retinal oximeter. Results: In the eye of the stenotic side, the retinal vessel oxygen saturation was 100.14 ± 10.27% in the arterioles and 56.50 ± 10.79% in the venules, and the arteriovenous (A‐V) difference was 43.63 ± 7.71%. In the eye of the contralateral side, the oxygen saturation was 96.55 ± 7.50% in the arterioles and 57.42 ± 9.84% in the venules, and the A‐V difference was 39.39 ± 6.33%. In healthy subjects, the oxygen saturation was 93.22 ± 5.98% in the arterioles and 56.57 ± 7.05% in the venules, and the A‐V difference was 36.65 ± 7.33%. The arteriolar oxygen saturation in the stenotic side was higher than that in the contralateral side (p = 0.025) and that in the healthy subjects (p = 0.027), and the A‐V difference in the stenotic side was significantly higher than that in the contralateral side (p = 0.009) and that in the healthy subjects (p = 0.013). The diameters of the arterioles in the stenotic side were smaller than those in the healthy subjects (p = 0.030). Conclusions: Patients with ICAS had decreased retinal arteriole diameters and increased retinal vessel oxygen saturation in the arterioles and A‐V differences, suggesting the presence of microcirculation disorder and hyperoxia in the retina. [ABSTRACT FROM AUTHOR]

The precise and effective generation and manipulation of micron‐sized droplets is crucial for chemical and biological research and applications. Normally, droplets generation and manipulation are achieved by two separate devices/systems with their respective operation strategies. Pipette, inkjet nozzle, and microfluidic channels equipped with programed syringes are commonly used for droplets generation whereas the subsequent manipulation is normally achieved by leveraging of forces originating either from optical, electric, magnetic or acoustic field and the corresponding complicated devices. Here we report a new paradigm that can realize simultaneous droplets generation and manipulation in an immiscible liquid environment using only the confined interface vibration generated by the ordinary inkjet nozzle. Droplets, ranging from femtoliter to picoliter, can be generated and manipulated without interruption since they are actuated by the same nozzle. Our strategy provides a platform for precise generation and manipulating the micro‐sized droplets that may be valuable for applications requiring simple setups and seamless connection between droplets generation and droplets manipulation. [ABSTRACT FROM AUTHOR]

Purpose: Variations in hydrocarbon composition and concentration are essential for the assessment of its source and environmental health in estuarine environments. This study aims to reveal the spatial and temporal distribution of multiple hydrocarbons in surface sediments of the Pearl River Estuary, and to further determine various sources of these hydrocarbons. Materials and methods: Surface sediments were taken monthly from four sites along a spatial transect from the Pearl River Estuary in a whole year by using a gravitational bottom sampler. A series of bulk parameters including the grain size, total organic carbon content, and total nitrogen content were measured. Hydrocarbons in sediments were extracted and analyzed by the gas chromatography-mass spectrometry. Results and discussion: The abundances of higher plants and phytoplankton-derived n-alkanes, petrogenically derived pristane, phytane, hopanes, and steranes with geological configuration, and anthropogenically derived hydrocarbons, including linear alkylbenzenes and polycyclic aromatic hydrocarbons all showed decreasing trends towards the coastal ocean. In contrast, the diatom-derived C25 highly branched isoprenoids increased towards saline sites. Monthly fluctuations of aliphatic and aromatic hydrocarbons at the estuarine mouth were smaller than the upstream freshwater sites, where high monthly variation (up to fivefold) was observed for most of the hydrocarbons detected. Conclusions: This study showed substantial monthly and spatial variations of hydrocarbons in the surface sediments of the Pearl River Estuary. Distribution and composition of sedimentary hydrocarbons indicate mainly anthropogenic inputs (e.g., petroleum residues and synthetic detergents) and terrestrially higher plants, followed by aquatic inputs. [ABSTRACT FROM AUTHOR]

Form grinding is the finishing process of the cycloid gear of RV reducer. In order to avoid the tooth surface burn of the cycloid gear during the grinding process and improve the grinding efficiency, the heat distribution ratio and the convection heat dissipation coefficient during the grinding process are calculated. The computer simulation software ANSYS 17.0 is used to calculate the instantaneous temperature field of the tooth surface during the grinding process of the cycloid gear. The distribution of the instantaneous temperature field of the tooth surface along the axial of the gear is obtained. According to the characteristics of the YK7350B gear grinding machine, the grinding process parameters is reasonably selected, and the grinding experiment is carried out. The metallographic structure of the burned section of the experimental part was observed by the ProgRes C5 metallographic measuring instrument to verify the simulation results. The research is beneficial to predict the temperature field distribution of the tooth surface of the cycloid gear and select the grinding process parameters reasonably. [ABSTRACT FROM AUTHOR]