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Efficient alkaline hydrogen evolution electrodes must be used for hydrogen production in anion exchange membrane water electrolyzers (AEMWEs). Therefore, we fabricated a NiMnS catalyst with a Mn-rich surface, which was self-supported on Ti paper through one-step electrodeposition. Mn doping endowed the catalyst with a unique hollow morphology and lattice-distorted structure. Consequently, the NiMnS/Ti electrode exhibited a large number of exposed electrochemical surfaces and effective active sites and a high hydrogen evolution reaction (HER) activity. Specifically, in half-cell measurements, the NiMnS/Ti electrode exhibited an overpotential of 65 mV at 10 mA cm−2, which was lower than that of NiS/Ti (102 mV) and indicated its superior HER activity. When the proposed cathode was applied in an AEMWE single cell, the device achieved a high current density of up to 0.9 A cm−2 at a cell potential of 2.0 V. [ABSTRACT FROM AUTHOR]

Developing highly efficient catalysts using facile approaches is important for accelerating the slow reaction kinetics of the alkaline hydrogen evolution reaction (HER) and ensuring cost-effective hydrogen production. In this study, we reported a facile alkali etching method to boost the HER activity immediately after electrodeposition of a NiFeZn catalyst on Ti paper. During etching, (oxy)hydroxides were formed on the surface, and Zn species were etched from the deposits, which resulted in a roughened surface with more valleys generated between grains, facilitating a faster mass transport during the electrochemical reaction. The etched catalyst exhibited a boosted HER overpotential of 57 mV at −10 mA/cm2 and accelerated HER kinetic with Tafel slope of 97 mV/dec compared with that of the pristine catalyst. Our results demonstrated an efficient approach for boosting the catalyst activity in the alkaline HER. [Display omitted] • NiFeZn electrocatalysts were prepared on Ti paper using electrodeposition method. • Their morphology and composition were controlled by varying deposition potential. • An alkali etching method is proposed to boost the pristine NiFeZn electrocatalyst. • The defect surface of NiFeZn generated by alkali etching improved HER activity. [ABSTRACT FROM AUTHOR]

To solve the issues of energy shortage and environmental pollution, it is essential to develop highly effective catalysts for hydrogen evolution reaction (HER) in water electrolysis. Herein, we report a facile and rapid fabrication of a Cu–Co–P catalyst on a carbon paper (CP) substrate using electrodeposition. First, the deposition conditions for Co–P/CP were optimized. The prepared Co–P consisted of numerous spheres and exhibited acceptable catalytic activity towards HER in an alkaline medium with an overpotential of 72 mV at current density of −10 mA/cm2. Further performance enhancement was achieved by the incorporation of Cu to modify the electronic structure of the Co–P catalyst. In a half-cell test, the optimized Cu–Co–P/CP exhibits remarkable performance, achieving −10 mA/cm2 at an overpotential of 59 mV, and the Tafel slope is 38 mV/dec. In a single-cell test, an anion exchange membrane water electrolyzer with a Cu–Co–P/CP cathode and commercial IrO 2 /CP anode exhibited high current density of 0.70 A/cm2 at 1.9 V cell. [Display omitted] • Cu–Co–P was electrodeposited on carbon paper while varying the Cu content. • The catalyst shows low overpotential of 59 mV to deliver −10 mA/cm2 and small Tafel slope in 1.0 M KOH. • The Cu–Co–P/CP gas diffusion electrode exhibited high cell performance (0.7 A/cm2 at 1.9 V cell) in AEMWE single cell. [ABSTRACT FROM AUTHOR]

Summary The development of an efficient water electrolyser is essential for sustainable hydrogen production; however, its application remains limited by the insufficient performance of the electrode. Herein, we report a rapid, simple, and cost‐effective fabrication of an Ni‐Co‐S cathode for the hydrogen evolution reaction (HER), which is directly usable for an anion exchange membrane water electrolyser (AEMWE). The Ni‐Co‐S electrocatalysts are prepared on a carbon paper (CP) substrate by a one‐step electrodeposition method by controlling deposition parameters such as the deposition potential, time, and electrolyte composition. The optimized Ni‐Co‐S/CP electrode demonstrates a high HER activity with an overpotential of 91 mV at −10 mA/cm2 in 1.0 M KOH. An AEMWE single cell employing the Ni‐Co‐S/CP cathode coupled with a commercial IrO2/CP anode exhibits a current density of 1.7 A/cm2 at 2.4 Vcell, which is higher than that of an AEMWE single cell with a commercial Pt/C/CP cathode; this is attributable to the enhancement of the electron and reactant/product transfer via appropriate cathode design. [ABSTRACT FROM AUTHOR]

• Co(OH) x /Ag/Co(OH) 2 nanosheet composites with sandwich structure were prepared. • Low overpotential of 283 mV at 10 mA/cm2 for OER is achieved. • AEMWE single cell with Co(OH) x /Ag/Co(OH) 2 anode electrode exhibits high cell performance (0.6 A/cm2 at 1.8 V). The sandwich-like Co(OH) x /Ag/Co(OH) 2 nanosheet composites fabricated by Ag galvanic displacement on the as-electrodeposited Co(OH) 2 layer and subsequent electrodeposition of the second Co(OH) 2 layer on carbon paper were directly applied as anode electrode in an anion exchange membrane water electrolyzer. [Display omitted] Development of efficient and durable materials for the oxygen evolution reaction (OER) is essential for hydrogen production via electrocatalytic water splitting. In this study, we demonstrated sandwich-like Co(OH) x /Ag/Co(OH) 2 nanosheet composites as efficient OER electrocatalysts in alkaline media. The composites were fabricated on carbon paper (CP) through Ag galvanic displacement on the as-electrodeposited Co(OH) 2 nanosheet layer and subsequent electrodeposition of the second Co(OH) 2 nanosheet layer. Benefiting from the introduction of Ag particles and the unique sandwich structure, the resulting composites exhibited excellent OER activity with the overpotential of 283 mV at the current density of 10 mA/cm2 and Tafel slope of 97 mV/dec in a 1.0 M KOH. Furthermore, an anion exchange membrane water electrolyzer employing the composite catalyst on CP as the anode, demonstrated a high cell performance with current density of 0.6 A/cm2 at 1.8 V. [ABSTRACT FROM AUTHOR]

It is important to consider the synergy of heterostructures to improve the slow kinetics of water dissociation in the alkaline hydrogen evolution reaction (HER). Herein, we report a simple method to design a heterohierarchical CoMo catalyst. The CoMo catalyst was prepared by simple one-pot electrodeposition on carbon paper (CP). The CoMo/CP catalyst was optimized for the alkaline HER by controlling the electrodeposition bath conditions, potential, and time. The optimized catalyst shows the heterohierarchical structure containing the electrically conductive metallic Co in the bulk and Mo-incorporated Co containing Mo4+ at the surface. It exhibited a lower HER overpotential of 0.11 V at −20 mA/cm2 compared to those of the others owing to the synergetic effect of the between the Co and Mo incorporated Co. The results highlight the advantages of the simple method developed herein for the design of heterohierarchical catalysts. [Display omitted] • A heterohierarchical CoMo catalyst is fabricated on carbon paper. • The optimized CoMo/CP shows a low HER overpotential of 0.11 V at −20 mA/cm2. • A facile method is proposed to design the heterostructured catalyst. [ABSTRACT FROM AUTHOR]

Summary: Carotenoids contribute to fruit coloration and are valuable sources of provitamin A in the human diet. Abscisic acid (ABA) plays an essential role in fruit coloration during citrus fruit ripening, but little is known about the underlying mechanisms. Here, we identified a novel bZIP transcription activator called CsbZIP44, which serves as a central regulator of ABA‐mediated citrus carotenoid biosynthesis. CsbZIP44 directly binds to the promoters of four carotenoid metabolism‐related genes (CsDXR, CsGGPPs, CsBCH1 and CsNCED2) and activates their expression. Furthermore, our research indicates that CsHB5, a positive regulator of ABA and carotenoid‐driven processes, activates the expression of CsbZIP44 by binding to its promoter. Additionally, CsHB5 interacts with CsbZIP44 to form a transcriptional regulatory module CsHB5‐CsbZIP44, which is responsive to ABA induction and promotes carotenoid accumulation in citrus. Interestingly, we also discover a positive feedback regulation loop between the ABA signal and carotenoid biosynthesis mediated by the CsHB5‐CsbZIP44 transcriptional regulatory module. Our findings show that CsHB5‐CsbZIP44 precisely modulates ABA signal‐mediated carotenoid metabolism, providing an effective strategy for quality improvement of citrus fruit and other crops. [ABSTRACT FROM AUTHOR]

There has been considerable research to engineer composites of transition metal dichalcogenides with other materials to improve their catalytic performance. In this work, we present a modified solution-processed method for the formation of molybdenum selenide (MoSe2) nanosheets and a facile method of structuring composites with graphene oxide (GO) or reduced graphene oxide (rGO) at different ratios to prevent aggregation of the MoSe2 nanosheets and hence improve their electrocatalytic hydrogen evolution reaction performance. The prepared GO, rGO, and MoSe2 nanosheets were characterized by X-ray powder diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. The electrocatalytic performance results showed that the pure MoSe2 nanosheets exhibited a somewhat high Tafel slope of 80 mV/dec, whereas the MoSe2-GO and MoSe2-rGO composites showed lower Tafel slopes of 57 and 67 mV/dec at ratios of 6:4 and 4:6, respectively. We attribute the improved catalytic effects to the better contact and faster carrier transfer between the edge of MoSe2 and the electrode due to the addition of GO or rGO. [ABSTRACT FROM AUTHOR]

Remaining useful life (RUL) prediction of rolling element bearings is critical to maintaining rotating machinery and lowering industrial costs. There are many RUL prediction techniques, but most of them ignore two factors that may have a significant impact on prediction accuracy. One is the detection of the first predicting time (FPT) while the other is the predictive uncertainty. This paper proposes a two-stage approach to incorporating both factors into the prediction process based on Bayesian deep learning (BDL). In stage one, the state change of the bearing is identified and the FPT is determined according to a proposed detection technique. In stage two, RUL prediction is performed according to a new BDL model, and the results provide RUL point estimates and quantification of predictive uncertainty. The proposed two-stage approach has been validated on two publicly available bearing datasets, and the experimental results have demonstrated the effectiveness of the proposed approach in detecting FPT and its superiority over competitive BDL models. • A new prediction framework has been proposed to address two issues in the process of predicting the RUL of bearings. • The two-stage approach achieves health stage division and RUL prediction of bearings by considering their degradation process. • The two-stage approach shows superior performance compared to other approaches on two separate stage tasks. [ABSTRACT FROM AUTHOR]

Conservation of crop wild relatives is critical for plant breeding and food security. The lack of clarity on the genetic factors that lead to endangered status or extinction create difficulties when attempting to develop concrete recommendations for conserving a citrus wild relative: the wild relatives of crops. Here, we evaluate the conservation of wild kumquat (Fortunella hindsii) using genomic, geographical, environmental, and phenotypic data, and forward simulations. Genome resequencing data from 73 accessions from the Fortunella genus were combined to investigate population structure, demography, inbreeding, introgression, and genetic load. Population structure was correlated with reproductive type (i.e., sexual and apomictic) and with a significant differentiation within the sexually reproducing population. The effective population size for one of the sexually reproducing subpopulations has recently declined to ~1,000, resulting in high levels of inbreeding. In particular, we found that 58% of the ecological niche overlapped between wild and cultivated populations and that there was extensive introgression into wild samples from cultivated populations. Interestingly, the introgression pattern and accumulation of genetic load may be influenced by the type of reproduction. In wild apomictic samples, the introgressed regions were primarily heterozygous, and genome-wide deleterious variants were hidden in the heterozygous state. In contrast, wild sexually reproducing samples carried a higher recessive deleterious burden. Furthermore, we also found that sexually reproducing samples were self-incompatible, which prevented the reduction of genetic diversity by selfing. Our population genomic analyses provide specific recommendations for distinct reproductive types and monitoring during conservation. This study highlights the genomic landscape of a wild relative of citrus and provides recommendations for the conservation of crop wild relatives. Author summary: Conservation genomics offers a comprehensive approach to understand the underlying genetic and environmental factors affecting the conservation of species. Despite its importance, the conservation genomics of most crop wild relatives remains poorly understood. In this study, we investigated the population fragmentation, inbreeding, gene flow, and genetic load of a citrus wild relative, Fortunella hindsii, using a combination of genomic, geographical, environmental, and phenotypic data, as well as forward simulations. Fortunella hindsii, listed on the registry of National Key Protected Wild Plants in China, has two types of reproduction, sexual and apomictic. Conservation genomics provided insights into the genetic diversity and structure, which are critical for developing effective conservation strategies. Our analysis also helped to assess the risks of hybridization and introgression from cultivated to wild populations. We found that different patterns of introgression and genetic load may be influenced by reproductive type; for example, deleterious variants may hide in the heterozygous state in apomictic populations. Sexually reproducing samples with the self-incompatibility mechanism can prevent rapid loss of genetic diversity caused by selfing. This study serves as an example of conservation genomics and the importance of utilizing important wild relatives of crops to inform broader conservation efforts. [ABSTRACT FROM AUTHOR]

Apomixis, or asexual seed formation, is prevalent in Citrinae via a mechanism termed nucellar or adventitious embryony. Here, multiple embryos of a maternal genotype form directly from nucellar cells in the ovule and can outcompete the developing zygotic embryo as they utilize the sexually derived endosperm for growth. Whilst nucellar embryony enables the propagation of clonal plants of maternal genetic constitution, it is also a barrier to effective breeding through hybridization. To address the genetics and evolution of apomixis in Citrinae , a chromosome-level genome of the Hongkong kumquat (Fortunella hindsii) was assembled following a genome-wide variation map including structural variants (SVs) based on 234 Citrinae accessions. This map revealed that hybrid citrus cultivars shelter genome-wide deleterious mutations and SVs into heterozygous states free from recessive selection, which may explain the capability of nucellar embryony in most cultivars during Citrinae diversification. Analyses revealed that parallel evolution may explain the repeated origin of apomixis in different genera of Citrinae. Within Fortunella , we found that apomixis of some varieties originated via introgression. In apomictic Fortunella , the locus associated with apomixis contains the FhRWP gene, encoding an RWP-RK domain-containing protein previously shown to be required for nucellar embryogenesis in Citrus. We found the heterozygous SV in the FhRWP and CitRWP promoters from apomictic Citrus and Fortunella , due to either two or three miniature inverted transposon element (MITE) insertions. A transcription factor, FhARID , encoding an AT-rich interaction domain-containing protein binds to the MITEs in the promoter of apomictic varieties, which facilitates induction of nucellar embryogenesis. This study provides evolutionary genomic and molecular insights into apomixis in Citrinae and has potential ramifications for citrus breeding. [ABSTRACT FROM AUTHOR]

Despite its importance for the establishment of a carbon‐neutral society, the electrochemical reduction of CO2 to value‐added products has not been commercialized yet because of its sluggish kinetics and low selectivity. The present work reports the fabrication of a low‐crystalline trimetallic (AuCuIn) CO2 electroreduction catalyst and demonstrates its high performance in a gaseous CO2 electrolyzer. The high Faradaic efficiency (FE) of CO formation observed at a low overpotential in a half‐cell test is ascribed to the controlled crystallinity and composition of this catalyst as well as to its faster charge transfer, downshifted d‐band center, and low oxophilicity. The gaseous CO2 electrolyzer with the optimal catalyst as the cathode exhibits superior cell performance with a high CO FE and production rate, outperforming state‐of‐the‐art analogs. Thus, the obtained results pave the way to the commercialization of CO2 electrolyzers and promote the establishment of a greener society. [ABSTRACT FROM AUTHOR]

This paper presents the investigation on possible chaotic motion in a vehicle suspension system with hysteretic non-linearity, which is subjected to the multi-frequency excitation from road surface. The Melnikov’s function is used to derive the critical condition for the chaotic motion, and then it is investigated that the effects of parameters in non-linear damping on the chaotic field. The path from quasi-periodic to chaotic motion is found via Poincare´ map and Lyapunov exponents. [Copyright &y& Elsevier]

Background: Fruit abortion is a major limiting factor for fruit production. In flat peach, fruit abortion is present in the whole tree of some accessions during early fruit development. However, the physiological factors and genetic mechanism underlying flat fruit abortion remain largely elusive. Results: In this study, we have revealed that the fertilization process was accomplished and the reduction of sucrose and starch contents might result in flat fruit abortion. By combining association and gene expression analysis, a key candidate gene, PpSnRK1βγ, was identified. A 1.67-Mb inversion co-segregated with flat fruit shape altered the promoter activity of PpSnRK1βγ, resulting in much lower expression in aborting flat peach. Ectopic transformation in tomato and transient overexpression in peach fruit have shown that PpSnRK1βγ could increase sugar and starch contents. Comparative transcriptome analysis further confirmed that PpSnRK1βγ participated in carbohydrate metabolism. Subcellular localization found that PpSnRK1βγ was located in nucleus. Conclusions: This study provides a possible reason for flat fruit abortion and identified a critical candidate gene, PpSnRK1βγ, that might be responsible for flat fruit abortion in peach. The results will provide great help in peach breeding and facilitate gene identification for fruit abortion in other plant species. [ABSTRACT FROM AUTHOR]

• A navel orange mutant 'Gannan No.1' has higher biomembrane stability and fruit quality during storage. • Higher unsaturation degree of fatty acids contributes to the membrane stability of citrus fruit. • The ascorbic acid-glutathione-tocopherol triad contributes to the anti-peroxidation of membrane lipids in citrus fruit. Little is known about the variations of fresh fruit biomembrane and its physiological and biochemical characteristics during storage. A navel orange mutant 'Gannan No.1' (Citrus sinensis Osbeck) showed higher membrane stability and titratable acid while lower calyx senescence compared with wild-type 'Newhall'. The membrane damage was significantly reduced in 'Gannan No.1' under 10% polyethylene-glycol (41.16% vs. 8.77%) and 30% polyethylene-glycol (52.59% vs. 16.11%) treatments on day 45 after harvest. Consistently, membrane electrolyte leakage and malondialdehyde were significantly decreased in 'Gannan No.1', and superoxide dismutase and glutathione reductase were activated. A metabolic analysis was performed to evaluate membrane fatty acid unsaturation and peroxidation. Linolenic acid and hexadecylenic acid contributed to the higher degree of unsaturated fatty acids in 'Gannan No.1'. Furthermore, 'Gannan No.1' accumulated stress-resistant metabolites such as proline, α-tocopherol and glutathione. Correlation analysis of membrane homeostasis indexes with quality parameters showed the importance of biomembrane stability in maintaining citrus fruit quality. [ABSTRACT FROM AUTHOR]

In this work, the microstructural evolution and its influence on the wear mechanism with the increasing Ti content are investigated in double-layer Al 0.5 CoCrFeNiSi 0.5 Ti x coatings. The results indicate that FCC solid solution as the matrix phase of first layer changes from cellular structure to columnar dendritic structure due to the addition of Ti. By contrast, BCC solid solution consisting of disordered BCC and ordered B2 are found to be the matrix phase of second layer. Ti promotes the transition of ordered B2 phase from speckle-shape to stripe-shape, and then to square-shape. Besides, Ti facilitates the in-situ synthesis of TiN and TiSi 2 in the Ti-containing coatings. Hardness of the coatings is dramatically improved due to the strengthening effect caused by Ti. The acting wear mechanism changes from abrasive wear of coating Ti0 to oxidational wear and mechanical mixing of Ti-containing coatings. The wear weight loss of the coatings decreases drastically with the increasing Ti content, indicating that the microstructural evolution caused by Ti addition has a positive influence on the wear resistance. • Phase compositions of Al 0.5 CoCrFeNiSi 0.5 Ti x HEA coatings are identified. • The microstructural evolution in response to the Ti addition is explored in detail. • The changes of wear mechanism induced by the increasing Ti content are determined. • The distorted microstructures under the worn surface are characterized. [ABSTRACT FROM AUTHOR]

Although the functions of carotenogenic genes are well documented, little is known about the mechanisms that regulate their expression, especially those genes involved in α - and β-branch carotenoid metabolism., In this study, an R2R3-MYB transcriptional factor (CrMYB68) that directly regulates the transformation of α- and β-branch carotenoids was identified using Green Ougan (MT), a stay-green mutant of Citrus reticulata cv Suavissima. A comprehensive analysis of developing and harvested fruits indicated that reduced expression of β-carotene hydroxylases 2 ( CrBCH2) and 9-cis-epoxycarotenoid dioxygenase 5 ( CrNCED5) was responsible for the delay in the transformation of α- and β-carotene and the biosynthesis of ABA. Additionally, the expression of these genes was negatively correlated with the expression of CrMYB68 in MT., Further, electrophoretic mobility shift assays (EMSAs) and dual luciferase assays indicated that CrMYB68 can directly and negatively regulate CrBCH2 and CrNCED5. Moreover, transient overexpression experiments using leaves of Nicotiana benthamiana indicated that CrMYB68 can also negatively regulate NbBCH2 and NbNCED5., To overcome the difficulty of transgenic validation, we quantified the concentrations of carotenoids and ABA, and gene expression in a revertant of MT. The results of these experiments provide more evidence that CrMYB68 is an important regulator of carotenoid metabolism. [ABSTRACT FROM AUTHOR]

• Genetic analysis indicated that the fruit skin color of sweet cherry was controlled by a single locus, and the yellow fruit skin color was recessive to blush and red. • Using a mapping-by-sequencing approach, a ∼90 kb deletion on chromosome 3 containing PavMYB10.1 TF was found to be an nonfunctional allele, PavMYB10.1 Del , responsible for responsible for anthocyanin deficiency in yellow-skinned varieties. • Two functional alleles of PavMYB10.1, PavMYB10.1a and PavMYB10.1b , causally lead to red or blush fruit skin color in sweet cherry. • Marker-trait association analysis revealed strong co-segregation of the fruit skin color phenotype and EFC markers in F 1 populations and a set of advanced breeding selections. Due to different accumulation and distribution patterns of anthocyanin, the fruits of sweet cherry (Prunus avium L.) display considerable color variation, ranging from yellow, blush to dark red. Yellow-skinned sweet cherries are characterized by the absence of anthocyanin in the fruits, providing a good candidate for research on yellow coloration in sweet cherry fruits. In this study, we identified the underlying genetic mechanism by integrating BSA-seq, RNA-seq, whole-genome sequencing and marker-trait association analyses. A ∼90 kb deletion on chromosome 3 containing PavMYB10.1 TF was found to be an nonfunctional allele, PavMYB10.1 Del , responsible for yellow fruit skin. Other two functional alleles of PavMYB10.1, PavMYB10.1a and PavMYB10.1b , result in red or blush skin color. Furthermore, evaluation of variant-trait association in F 1 populations and a set of advanced breeding selections revealed strong co-segregation of the fruit skin color phenotypes and the EFC marker which combined by primers specific to PavMYB10.1a/b and PavMYB10.1 Del separately. These results provide novel insights into yellow fruit skin coloration in sweet cherry and represent a useful tool for the pre-selection of fruit color in molecular-assisted breeding programs. [ABSTRACT FROM AUTHOR]

Due to the furanocoumarin compounds in the fruit, the production and consumption of grapefruit have been affected in the past decades since the ‘grapefruit juice effect’ was declared. To provide elite germplasm and obtain knowledge for future citrus breeding programs, the contents of 4 furanocoumarin monomers (FCMs) in the juice sacs from 73 citrus germplasms were evaluated using ultra-performance liquid chromatography. 6′,7′-Dihydroxybergamottin and bergamottin were dominant in all the tested grapefruits, while there were some pomelos with dominant epoxybergamottin, and some with dominant 6′,7′-dihydroxybergamottin and bergamottin. The contents of FCMs were low or below detection in sweet oranges, mandarins, lemons and trifoliate oranges. The results also show that the dominant patterns of FCMs are genotype-related, and crossing and selection are effective approaches to alter FCM profiles in citrus breeding. Furthermore, the contribution of pomelo as a parent to grapefruit regarding their FCM profiles was discussed. [ABSTRACT FROM AUTHOR]

Abstract: Pummelo (Citrus grandis Osbeck) is one of the ancestors of sweet orange and economically important cultivated species of the family Rutaceae. The availability of the EST SSR markers for Pummelo represents a promising source to increase the number of markers available for the citrus species. In this study, we evaluated 212 Pummelo EST derived SSR markers (CgEMS) for their transferability across the genera, polymorphism, mapping ability and utility for genetic diversity analysis. Among these markers, 136 were amplified bands, 99 were transferable across the genera. Transferability of CgEMS to C. sinensis, C. reticulata, C. lemon, Fortunella sp and Poncirus sp was 76%, 76%, 75%, 74% and 73%, respectively. In contrast 52 (53%) markers were found to be polymorphic and segregating in a mapping population. Segregating markers can be categorized into four groups: full informative (8%), male informative (15%), female informative (19%) and partly informative (59%). The phylogenetic relationship between the citrus and its relatives obtained with CgEMS was in a good agreement with the established citrus taxonomy and phylogeny. CgEMS could potentially serve as perfect markers for determining variation in phenotype, fingerprinting, mapping and genetic diversity study in C. grandis. Their high level of cross genera transferability of the CgEMS markers has allowed phylogenetic inference within the Rutaceae. [Copyright &y& Elsevier]

Abstract: Somatic hybridization provides an alternative for transferring mitochondria-encoded cytoplasmic male sterility (CMS). Herein, symmetric protoplast electrofusion was conducted between embryogenic callus protoplasts of Citrus unshiu Marc. cv. Guoqing No. 1 (G1), a CMS cultivar, and mesophyll-derived protoplasts of seedy ‘Page’ tangelo [C. reticulata Blanco×(C. reticulata Blanco× C. paradisi Macf.)] or ‘Nova’ tangelo [C. reticulata Blanco×(C. reticulata Blanco× C. paradisi Macf.)], to transfer CMS trait. Flow cytometry analysis showed that 14 plants recovered from G1+‘Page’ tangelo that displayed typical morphological character of ‘Page’ were diploid, and 6 plants regenerated from G1+‘Nova’ tangelo were tetraploid. Genetic compositions of regenerated plants from the two fusions were determined by SSR, CAPS and chloroplast-SSR analysis. Cybrid nature of diploids from G1+‘Page’ tangelo with nuclear DNA from ‘Page’, mitochondrial DNA (mtDNA) from the G1 and chloroplast DNA (cpDNA) derived from either parent was confirmed. Tetraploid plants from G1+‘Nova’ tangelo were identified as somatic hybrids with random cpDNA inheritance. The regenerated cybrid and hybrid plants hold great potential for Citrus seedless breeding at diploid or triploid levels. [Copyright &y& Elsevier]

Abstract: The precocious trifoliate orange (Poncirus trifoliata [L.] Raf.), an early flowering mutant of P. trifoliata, has a short juvenile phase of about 14 months, significantly shorter than other citrus. In this report, using the stems of precocious trifoliate orange seedlings as explants, an improved protocol mediated by Agrobacterium tumefaciens was developed to evaluate regeneration and transformation frequency. The transformed plants continued to reveal the precocious trait of non-transgenic mature precocious trifoliate orange, and as such could prove to be an efficient system for the verification of gene function in the fruits/flower via genetic transformation in woody plants. [Copyright &y& Elsevier]

No presently available rootstock combines all the available rootstock attributes necessary for efficient long-term citriculture (production and harvesting) of Mexican limes and other commercially important scions. In the present study, somatic hybridization techniques were used to combine the widely adapted Amblycarpa mandarin (also known as Nasnaran mandarin) with six different trifoliate/trifoliate hybrid selections: Benton, Carrizo, and C-35 citranges; Flying Dragon and Rubidoux trifoliate oranges; and a somatic hybrid of sour orange + Flying Dragon. The ultimate goal of this research is to generate polyploid somatic hybrids that express the complementary horticultural and disease resistance attributes of the corresponding parents, and have direct potential as improved tree-size controlling rootstocks. Somatic hybrids from all six parental combinations were confirmed by a combination of leaf morphology, flow cytometry, and randomly amplified polymorphic DNA (RAPD) (for nuclear hybridity) and cleaved amplified polymorphic sequence (CAPS) analyses (for mtDNA and cpDNA). This is the first report of citrus somatic hybridization using Amblycarpa mandarin. Unexpected hexapioid somatic hybrid plants were recovered from the fusion of Amblycarpa mandarin + C-35 citrange. Hexapioid hybrids should be very dwarfing and may have potential for producing potted ornamental citrus. Resulting somatic hybrid plants from all six combinations have been propagated by tissue culture and/or rooted cuttings and are being prepared for commercial field evaluation for their potential as improved rootstocks for Mexican lime and other important scions. [ABSTRACT FROM AUTHOR]

• Ir loading on Au dendrite is simply controlled in micro-gram scale. • Specific OER activities are significantly affected by Ir electronic structure. • Extremely high OER mass activities are obtained in half cell and single cell test. • They significantly exceed the mass activities of state-of-the-art Ir-based anodes. The insufficient performance of current oxygen evolution reaction (OER) electrodes limits the realization of clean hydrogen production via proton exchange membrane water electrolyzers (PEMWEs). Herein, an innovative electrode design with an ultra-low Ir loading is proposed to achieve high catalytic OER performance, catalyst utilization, conductivity, and mass transfer. The microgram-scale loading of Ir on a highly roughened dendritic Au support is controlled by the number of Ir deposition pulses and, together with Ir coverage, which significantly affect the Ir electronic structure and intrinsic OER activity. Further control of the Ir electronic structure is achieved by forming Ir oxides via electrochemical and thermal oxidation to adjust the activity–stability balance. A PEMWE employing the fabricated electrode demonstrates substantially low ohmic and mass-transfer losses, especially in the higher-current-density region. As a result, superior cell performance with extremely high mass activity is achieved, significantly exceeding the mass activities of state-of-the-art Ir-based anodes. [ABSTRACT FROM AUTHOR]