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The development of inductive fault current limiters up to 100kVAV class prototype is described. Current limitation was derived through a progressive transition of the superconducting high temperature superconductor Bi-2212 tube(s) to a resistive state. The simulation of the inductive limiter behavior using differential equations are presented where both electromagnetic and thermal behavior are taken into account.

Fast acting high temperature superconducting fault current limiters were tested and simulated. Tests were conducted on 43kVA nominal power, 350V rms and 95A rms systems and results were compared to theoretical simulations. Design considerations and superconducting material properties were examined through circuit analysis. Limiter reliability was ensured by using homogeneous materials.

A study was conducted on the factors that influence the uniformity of thin filaments Bi-2223/Ag superconducting tapes. Non-uniformities were found to be caused by shear fracture, sausaging and tensile fracture in the oxide core. These defects were theoretically explained as a function of the stress-dependent mechanical properties of superconducting powders. Results demonstrate that uniformity is enhanced by small roller size and low reduction rates during flat rolling.

A four-point sliding contact was employed to quantify the longitudinal and transverse components of the surface potential along several centimeters of a silver-clad Bi-2223 tape for 'fixed values of current and external fields.' The instrument, which may be used to construct voltage-current curves, enabled a correlation between microstructure and superconducting performance to be drawn from the presence of 'deliberately included defects.'

The paralogous genes INCURVATA11 ( ICU11 ) and CUPULIFORMIS2 ( CP2 ) encode components of the epigenetic machinery in Arabidopsis and belong to the 2-oxoglutarate and Fe (II)-dependent dioxygenase superfamily. We previously inferred unequal functional redundancy between ICU11 and CP2 from a study of the synergistic phenotypes of the double mutant and sesquimutant combinations of icu11 and cp2 mutations, although they represented mixed genetic backgrounds. To avoid potential confounding effects arising from different genetic backgrounds, we generated the icu11-5 and icu11-6 mutants via CRISPR/Cas genome editing in the Col-0 background and crossed them to cp2 mutants in Col-0. The resulting mutants exhibited a postembryonic-lethal phenotype reminiscent of strong embryonic flower ( emf ) mutants. Double mutants involving icu11-5 and mutations affecting epigenetic machinery components displayed synergistic phenotypes, whereas cp2-3 did not besides icu11-5 . Our results confirmed the unequal functional redundancy between ICU11 and CP2 and demonstrated that it is not allele or genetic background specific. An increase in sucrose content in the culture medium partially rescued the post-germinative lethality of icu11 cp2 double mutants and sesquimutants, facilitating the study of their morphological phenotypes throughout their life cycle, which include floral organ homeotic transformations. We thus established that the ICU11-CP2 module is required for proper flower organ identity., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Nadi, Juan-Vicente, Mateo-Bonmatí and Micol.)

The N 6 -methyladenosine (m 6 A) pathway has been widely described as a viral regulatory mechanism in animals. We previously reported that the capsid protein (CP) of alfalfa mosaic virus (AMV) interacts with the Arabidopsis m 6 A demethylase ALKBH9B regulating m 6 A abundance on viral RNAs (vRNAs) and systemic invasion of floral stems. Here, we analyze the involvement of other ALKBH9 proteins in AMV infection and we carry out a detailed evaluation of the infection restraint observed in alkbh9b mutant plants. Thus, via viral titer quantification experiments and in situ hybridization assays, we define the viral cycle steps that are altered by the absence of the m 6 A demethylase ALKBH9B in Arabidopsis. We found that ALKBH9A and ALKBH9C do not regulate the AMV cycle, so ALKBH9B activity seems to be highly specific. We also define that not only systemic movement is affected by the absence of the demethylase, but also early stages of viral infection. Moreover, our findings suggest that viral upload into the phloem could be blocked in alkbh9b plants. Overall, our results point to ALKBH9B as a possible new component of phloem transport, at least for AMV, and as a potential target to obtain virus resistance crops., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Martínez-Pérez, Gómez-Mena, Alvarado-Marchena, Nadi, Micol, Pallas and Aparicio.)

Flavor traits in citrus are the result of a blend of low molecular weight metabolites including sugars, acids, flavonoids and limonoids, these latter being mainly responsible for the characteristic bitter flavor in citrus. In this work, the genotype- and developmental stage-dependent accumulation of flavonoids and limonoids is addressed. To fulfill this goal, three models for citrus bitterness: bitter Duncan grapefruit, bittersweet Thomson orange and sweet Wase mandarin were selected from a total of eight different varieties. Compounds were annotated from LC/ESI-QqTOF-MS non-targeted metabolite profiles from albedo and pulp tissues. Results indicated that the specific blend of compounds providing the characteristic flavor trait is genotype-specific and hence under genetic control, but it is also regulated at the developmental level. Metabolite profiles in albedo mirrored those found in pulp, the edible part of the fruit, despite differences in the concentration and accumulation/depletion rates being found. This is particularly relevant for polymethoxylated flavones and glycosylated limonoids that showed a clear partitioning towards albedo and pulp tissues, respectively. Fruit ripening was characterized by a reduction in flavonoids and the accumulation of limonoid glycosides. However, bitter grapefruit showed higher levels of limonin A-ring lactone and naringin in contrast to sweeter orange and mandarin. Data indicated that the accumulation profile was compound class-specific and conserved among the studied varieties despite differing in the respective accumulation and/or depletion rate, leading to different specialized metabolite concentration at the full ripe stage, consistent with the flavor trait output.

All critical developmental and physiological events in a plant's life cycle depend on the proper activation and repression of specific gene sets, and this often involves epigenetic mechanisms. Some Arabidopsis thaliana mutants with disorders of the epigenetic machinery exhibit pleiotropic defects, including incurved leaves and early flowering, due to the ectopic and heterochronic derepression of developmental regulators. Here, we studied one such mutant class, the incurvata11 ( icu11 ) loss-of-function mutants. We have identified ICU11 as the founding member of a small gene family that we have named CUPULIFORMIS ( CP ). This family is part of the 2-oxoglutarate/Fe(II)-dependent dioxygenase superfamily. ICU11 and its closest paralog, CP2, have unequally redundant functions: although cp2 mutants are phenotypically wild type, icu11 cp2 double mutants skip vegetative development and flower upon germination. This phenotype is reminiscent of loss-of-function mutants of the Polycomb-group genes EMBRYONIC FLOWER1 ( EMF1 ) and EMF2 Double mutants harboring icu11 alleles and loss-of-function alleles of genes encoding components of the epigenetic machinery exhibit synergistic, severe phenotypes, and some are similar to those of emf mutants. Hundreds of genes are misexpressed in icu11 plants, including SEPALLATA3 ( SEP3 ), and derepression of SEP3 causes the leaf phenotype of icu11 ICU11 and CP2 are nucleoplasmic proteins that act as epigenetic repressors through an unknown mechanism involving histone modification, but not DNA methylation., (© 2018 American Society of Plant Biologists. All rights reserved.)

The CRISPR/Cas9 system and related RNA-guided endonucleases can introduce double-strand breaks (DSBs) at specific sites in the genome, allowing the generation of targeted mutations in one or more genes as well as more complex genomic rearrangements. Modifications of the canonical CRISPR/Cas9 system from Streptococcus pyogenes and the introduction of related systems from other bacteria have increased the diversity of genomic sites that can be targeted, providing greater control over the resolution of DSBs, the targeting efficiency (frequency of on-target mutations), the targeting accuracy (likelihood of off-target mutations) and the type of mutations that are induced. Although much is now known about the principles of CRISPR/Cas9 genome editing, the likelihood of different outcomes is species-dependent and there have been few comparative studies looking at the basis of such diversity. Here we critically analyse the activity of CRISPR/Cas9 and related systems in different plant species and compare the outcomes in animals and microbes to draw broad conclusions about the design principles required for effective genome editing in different organisms. These principles will be important for the commercial development of crops, farm animals, animal disease models and novel microbial strains using CRISPR/Cas9 and other genome-editing tools., (© 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.)