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Garlic (Allium sativum L.), an asexually propagated vegetable and medicinal crop, has abundant genetic variation. Genetic diversity evaluation based on molecular markers has apparent advantages since their genomic abundance, environment insensitivity, and non-tissue specific features. However, the limited number of available DNA markers, especially SSR markers, are insufficient to conduct related genetic diversity assessment studies in garlic. In this study, 4372 EST-SSR markers were newly developed, and 12 polymorphic markers together with other 17 garlic SSR markers were used to assess the genetic diversity and population structure of 127 garlic accessions. The averaged polymorphism information content (PIC) of these 29 SSR markers was 0.36, ranging from 0.22 to 0.49. Seventy-nine polymorphic loci were detected among these accessions, with an average of 3.48 polymorphic loci per SSR. Both the clustering analyses based on either the genotype data of SSR markers or the phenotypic data of morphological traits obtained genetic distance divided the 127 garlic accessions into three clusters. Moreover, the Mantel test showed that genetic distance had no significant correlations with geographic distance, and weak correlations were found between genetic distance and the phenotypic traits. AMOVA analysis showed that the main genetic variation of this garlic germplasm collection existed in the within-population or cluster. Results of this study will be of great value for the genetic/breeding studies in garlic and enhance the utilization of these garlic germplasms.

In Arabidopsis, the photoreceptors phytochrome B- (PhyB) and UVB resistance 8- (UVR8) mediated light responses play a major role in regulating photomorphogenic hypocotyl growth, but how they crosstalk to coordinate this process is not well understood. Here we report map-based cloning and functional characterization of a UVB-insensitive, long-hypocotyl mutant, lh1, and a wild-type-like lh2 mutant in cucumber, Cucumis sativus, which encodes a defective CsPhyB and a key gibberellic acid (GA) biosynthesis enzyme CsGA20ox-2, respectively. The lh2 mutation was epistatic to lh1 and partly suppressed long-hypocotyl phenotype in the lhl1lh2 double mutant. We identified phytochrome interacting factor (PIF) CsPIF3 that played a critical role in integrating the red/far-red and UVB light responses for hypocotyl growth. We show that two modules, CsPhyB-CsPIF3-CsGA20ox-2 (GA oxidase2)-DELLA and CsPIF3-CsARF18 (auxin response factor 18) mediate CsPhyB-regulated hypocotyl elongation through GA and auxin pathways, respectively, in which CsPIF3 binds to the G-/E-box motifs in the promoters of CsGA20ox-2 and CsARF18 to regulate their expression. We also identified a new physical interaction between CsPIF3 and CsUVR8 mediating CsPhyB-dependent, UVB-induced hypocotyl growth inhibition. Our work suggests that hypocotyl growth in cucumber involves a complex interplay of multiple photoreceptor- and phytohormone-mediated signaling pathways that show both conservation with and divergence from those in Arabidopsis.

Fruit length is a key domestication trait that affects crop yield and appearance. Cucumber (Cucumis sativus) fruits vary from 5 to 60 cm in length. Despite the identification of several regulators and multiple quantitative trait loci (QTLs) underlying fruit length, the natural variation, and molecular mechanisms underlying differences in fruit length are poorly understood. Through map-based cloning, we identified a nonsynonymous polymorphism (G to A) in CRABS CLAW (CsCRC) as underlying the major-effect fruit size/shape QTL FS5.2 in cucumber. The short-fruit allele CsCRCA is a rare allele that has only been found in round-fruited semi-wild Xishuangbanna cucumbers. A near-isogenic line (NIL) homozygous for CsCRCA exhibited a 34∼39% reduction in fruit length. Introducing CsCRCG into this NIL rescued the short-fruit phenotype, and knockdown of CsCRCG resulted in shorter fruit and smaller cells. In natural cucumber populations, CsCRCG expression was positively correlated with fruit length. Further, CsCRCG, but not CsCRCA, targets the downstream auxin-responsive protein gene CsARP1 to regulate its expression. Knockout of CsARP1 produced shorter fruit with smaller cells. Hence, our work suggests that CsCRCG positively regulates fruit elongation through transcriptional activation of CsARP1 and thus enhances cell expansion. Using different CsCRC alleles provides a strategy to manipulate fruit length in cucumber breeding.

The compact (cp) phenotype in cucumber (Cucumis sativus L.) is an important plant architecture-related trait with a great potential for cucumber improvement. In this study, we conducted map-based cloning of the cp locus, identified and functionally characterized the candidate gene. Comparative microscopic analysis suggested that the short internode in the cp mutant is due to fewer cell numbers. Fine genetic mapping delimited cp into an 8.8-kb region on chromosome 4 harboring only one gene, CsERECTA (CsER) that encodes a leucine rich repeat receptor-like kinase. The insertion of a 5.5-kb insertion of along terminal repeat retrotransposon in the 22nd exon resulted in loss-of-function of CsER in the cp plant. Spatiotemporal expression analysis in cucumber and CsER promoter-driven GUS assays in Arabidopsis indicated that CsER was highly expressed in the stem apical meristem and young organs, but the expression level was similar in the wild type and mutant cucumber plants. However, CsER protein accumulation was reduced in the mutant as revealed by western hybridization. The mutation in cp also did not seem to affect self-association of CsER for formation of dimers. Ectopic expression of CsER in Arabidopsis was able to rescue the plant height of the loss-of-function AtERECTA mutant, whereas the compact inflorescence and small rosette leaves of the mutant could be partially recovered. Transcriptome profiling in the mutant and wild type plants revealed hormone biosynthesis/or signaling, and photosynthesis pathways associated with CsER-dependent regulatory network. Our work from the present study provides new insights for the use of cp in cucumber breeding.

We report a comprehensive study on the elastic properties of a hexanary high-entropy alloy superconductor (ScZrNbTa)$_{0.685}$[RhPd]$_{0.315}$ at room and cryogenic temperatures, by Resonant Ultrasound Spectroscopy experiments. The derived elastic constants are bulk modulus $K=132.7$ GPa, Young's modulus $E=121.0$ GPa, shear modulus $G=44.9$ GPa, and Poisson's ratio $\nu$=0.348 for room temperature. The Young's and shear moduli are $\sim 10\%$ larger than those in NbTi superconductor with similar $T_c$, while the ductility is comparable. Moreover, the mechanical performance is further enhanced at cryogenic temperature. Our work confirms the advantageous mechanical properties of high-entropy alloy superconductors and suggests the application prospects., Comment: 11 pages, 3 figures, 1 table

Garlic, an economically important vegetable, spice, and medicinal crop, produces highly enlarged bulbs and unique organosulfur compounds. Here, we report a chromosome-level genome assembly for garlic, with a total size of approximately 16.24 Gb, as well as the annotation of 57 561 predicted protein-coding genes, making garlic the first Allium species with a sequenced genome. Analysis of this garlic genome assembly reveals a recent burst of transposable elements, explaining the substantial expansion of the garlic genome. We examined the evolution of certain genes associated with the biosynthesis of allicin and inulin neoseries-type fructans, and provided new insights into the biosynthesis of these two compounds. Furthermore, a large-scale transcriptome was produced to characterize the expression patterns of garlic genes in different tissues and at various growth stages of enlarged bulbs. The reference genome and large-scale transcriptome data generated in this study provide valuable new resources for research on garlic biology and breeding.

A simple and green reaction was discovered for iodization–methylsulfoxidation of alkynes to access (E)-α-iodo-β-methylsulfonylalkenes. This is the first report for the synthesis of iodovinyl methyl...

Fruit length is a prominent agricultural trait during cucumber (Cucumis sativus) domestication and diversifying selection; however, the regulatory mechanisms of fruit elongation remain elusive. We identified two alleles of the FRUITFULL (FUL)–like MADS-box gene CsFUL1 with 3393(C/A) Single Nucleotide Polymorphism variation among 150 cucumber lines. Whereas CsFUL1(A) was specifically enriched in the long-fruited East Asian type cucumbers (China and Japan), the CsFUL1(C) allele was randomly distributed in cucumber populations, including wild and semiwild cucumbers. CsFUL1(A) knockdown led to further fruit elongation in cucumber, whereas elevated expression of CsFUL1(A) resulted in significantly shorter fruits. No effect on fruit elongation was detected when CsFUL1(C) expression was modulated, suggesting that CsFUL1(A) is a gain-of-function allele in long-fruited cucumber that acts as a repressor during diversifying selection of East Asian cucumbers. Furthermore, CsFUL1(A) binds to the CArG-box in the promoter region of SUPERMAN, a regulator of cell division and expansion, to repress its expression. Additionally, CsFUL1(A) inhibits the expression of auxin transporters PIN-FORMED1 (PIN1) and PIN7, resulting in decreases in auxin accumulation in fruits. Together, our work identifies an agriculturally important allele and suggests a strategy for manipulating fruit length in cucumber breeding that involves modulation of CsFUL1(A) expression.

Salt metathesis reactions between pyridyl-methylene-cyclopentadienyl lithium salt and LnCl3 followed by the addition of two equivalents of LiCH2SiMe3 afforded a series of constrained-geometry-configuration rare-earth metal bis(alkyl) complexes (Cp′CH2- Py)Ln(CH2SiMe3)2(THF)n (Py = C5H4N, Cp′ = C5H4 (Cp), Ln = Sc, n = 0 (1); Cp′ = C9H6 (Ind), Ln = Sc, n = 0 (2); Cp′ = 3-Me3Si-C9H5 (3-Me3Si-Ind), Ln = Sc, n = 0 (3a), Ln = Lu (3b), Y (3c), n = 1; Cp′ = 2,7-(tBu)2C13H8 (2,7-(tBu)2-Flu), Ln = Sc (4a), n = 0, Ln = Lu (4b), Y (4c), n = 1) in moderate to good yields, which were characterized by NMR spectroscopy and single-crystal X-ray diffraction (for complex 3a). In the presence of [Ph3C][B(C6F5)4] and AliBu3, these complexes displayed different performances towards styrene polymerization. Rare-earth metal bis(alkyl) precursors bearing Cp, Ind, and 3-Me3Si-Ind segments exhibited very low catalytic activity to afford syndiotactic polystyrene. All electron-donating tBu substituted complexes 4a, 4b, and 4c showed very high activity and perfect syndiotactivity (rrrr > 99%), producing high molecular weight polystyrene (up to 54.1 × 104) with relatively narrow molecular distribution (PDI = 1.28−2.49).

PN3P-Ir pincer hydride complexes were synthesized and characterized as catalysts and key intermediates in the direct hydrogenation of CO2 to formate under mild conditions. The formation of a dearomatized PN3P*-Ir(i)-CO species was identified as a plausible key process accountable for the loss of catalytic activity in the CO2 hydrogenation.

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Fruit size and shape are important qualities and yield traits in cucumber (Cucumis sativus L.), but the factors that influence fruit size and shape remain to be explored. In this study, we investigated the dynamic changes of fruit size and shape from the aspects of morphology, cellular levels and endogenous hormones for nine typical cucumber inbred lines. The results show that fruit length had a strong positive correlation to the cell number in the longitudinal section of fruit throughout the four stages of 0, 6, 12, and 30 DAA (days after anthesis). However, the significant negative correlations were found between fruit length and the fruit cell size at 12 and 30 DAA. Furthermore, fruit diameter was positively correlated to the cell number in the cross section at all the investigated fruit growth stages. The indole-3-acetic acid (IAA) content showed significant positive correlations to the fruit length at all fruit growth stages of &minus, 6, &minus, 3, 0, 3, 6, 9 and 12 DAA, but IAA content and fruit diameter showed significant negative correlations for all the stages except for at &minus, 6 DAA. The trans-zeatin riboside (tZR), zeatin (ZT), gibberellic acid (GA3) and jasmonic acid (JA) content had a positive or negative correlation with fruit length or diameter only at certain stages. Neither fruit length nor diameter had significant correlations to abscisic acid (ABA) content. These results indicate that variations in fruit size and shape of different cucumber inbred lines mainly result from the differences in fruit cell number and endogenous IAA content. The present work is the first to propose cucumber fruit size and shape changes from the combined aspects of morphology, cellular levels, and endogenous hormones.

The molecular structure of a catalytically active key intermediate is determined in solution by employing 2D IR spectroscopy measuring vibrational cross-angles. The formate intermediate (2) in the formic acid dehydrogenation reaction catalyzed by a phosphorus–nitrogen PN(3)P–Ru catalyst is elucidated. Our spectroscopic studies show that the complex features a formate ion directly attached to the Ru center as a ligand, and a proton added to the imine arm of the dearomatized PN(3)P* ligand. During the catalytic process, the imine arms are not only reversibly protonated and deprotonated, but also interacting with the protic substrate molecules, effectively serving as the local proton buffer to offer remarkable stability with a turnover number (TON) over one million.

Formic acid (FA) has been extensively studied as one of the most promising hydrogen energy carriers today. The catalytic decarboxylation of FA ideally leads to the formation of CO2 and H2 that can be applied in fuel cells. A large number of transition-metal based homogeneous catalysts with high activity and selectivity have been reported for the selective FA dehydrogentaion. In this review, we discussed the recent development of C,N/N,N-ligand and pincer ligand-based homogeneous catalysts for the FA dehydrogenation reaction. Some representative catalysts are further evaluated by the CON/COF assessment (catalyst on-cost number)/(catalyst on-cost frequency). Conclusive remarks are provided with future challenges and opportunities.

Plants employ tight genetic control to integrate intrinsic growth signals and environmental cues to enable organs to grow to a defined size. Many genes contributing to cell proliferation and/or cell expansion, and consequently organ size control, have been identified, but the regulatory pathways are poorly understood. Here we have characterized a cucumber littleleaf (ll) mutant which exhibits smaller organ sizes but more lateral branches than the wild type. The small organ size in ll was due to a reduction of both cell number and cell size. Quantitative trait locus (QTL) analyses revealed co-localization of major-effect QTLs for fruit size, fruit and seed weight, as well as number of lateral branches, with the LL locus indicating pleiotropic effects of the ll mutation. We demonstrate that LL is an ortholog of Arabidopsis STERILE APETALA (SAP) encoding a WD40 repeat domain-containing protein; the mutant protein differed from the wild type by a single amino acid substitution (W264G) in the second WD40 repeat. W264 was conserved in 34 vascular plant genomes examined. Phylogenetic analysis suggested that LL originated before the emergence of flowering plants but was lost in the grass genome lineage. The function of LL in organ size control was confirmed by its overexpression in transgenic cucumbers and ectopic expression in Arabidopsis. Transcriptome profiling in LL and ll bulks revealed a complex regulatory network for LL-mediated organ size variation that involves several known organ size regulators and associated pathways. The data support LL as an important player in organ size control and lateral branch development in cucumber.

A post-modification strategy is used to synthesize a new class of diimine-amido PN3P-pincer group-10 transition metal complexes. The coordination chemistry and the thermal stabilities of their organometallic derivatives are characterized and investigated.

A simple and green reaction was discovered for iodization-methylsulfoxidation of alkynes to access (

An unsymmetrically protonated PN(3) -pincer complex in which ruthenium is coordinated by one nitrogen and two phosphorus atoms was employed for the selective generation of hydrogen from formic acid. Mechanistic studies suggest that the imine arm participates in the formic acid activation/deprotonation step. A long life time of 150 h with a turnover number over 1 million was achieved.

The WUSCHEL-related homeobox1 (WOX1) transcription factor plays an important role in lateral growth of plant organs; however, the underlying mechanisms in the regulation of reproductive development are largely unknown. Cucumber (Cucumis sativus) has separate male and female flowers, facilitating the study of the role of WOX1 in stamen and carpel development. Here, we identified a mango fruit (mf) mutant in cucumber, which displayed multiple defects in flower growth as well as male and female sterility. Map-based cloning showed that Mf encodes a WOX1-type transcriptional regulator (CsWOX1), and that the mf mutant encodes a truncated protein lacking the conserved WUS box. Further analysis showed that elevated expression of CsWOX1 was responsible for the mutant phenotype in cucumber and Arabidopsis. Comparative transcriptome profiling revealed certain key players and CsWOX1-associated networks that regulate reproductive development. CsWOX1 directly interacts with cucumber SPOROCYTELESS (CsSPL), and many genes in the CsSPL-mediated pathway were down-regulated in plants with the mutant allele at the Mf locus. In addition, auxin distribution was affected in both male and female flowers of the mutant. Taking together, these data suggest that CsWOX1 may regulate early reproductive organ development and be involved in sporogenesis via the CsSPL-mediated pathway and/or modulate auxin signaling in cucumber.

A neutral complex PN(3)P-Rh(I)Cl (2) was prepared from a reaction of the PN(3)P pincer ligand (1) with [Rh(COD)Cl]2 (COD = 1,5-cyclooctadiene). Upon treatment with a suitable base, H-H and C(sp(2))-H activation reactions can be achieved through the deprotonation/reprotonation of one of the N-H arms and dearomatization/rearomatization of the central pyridine ring with the oxidation state of Rh remaining I.

The dwarf or compact plant architecture is an important trait in plant breeding. A number of genes controlling plant height have been cloned and functionally characterized which often involve in biosynthesis or signaling of plant hormones such as brassinosteroids (BRs). No genes for plant height or vine length have been cloned in cucurbit crops (family Cucurbitaceae). From an EMS-induced mutagenesis population, we identified a super compact (SCP) mutant C257 which was extremely dwarf due to practically no internode elongation. Under dark growing condition, C257 did not undergo skotomorphogenesis and its mutant phenotype could be rescued with exogenous application of brassinolide, suggesting SCP might be a BR-deficient mutant. Segregation analysis revealed a single recessive gene scp-1 that was responsible for the SCP mutation. Map-based cloning combined with a modified MutMap identified CsCYP85A1, a member of the plant cytochrome P450 monooxygenase gene family, as the most possible candidate gene for scp-1, which encodes a BR-C6-oxidase in the BR biosynthesis pathway. We show that a SNP within the second exon of scp-1 candidate gene caused the SCP phenotype. Three copies of the CsCYP85A gene are present in the cucumber genome, but only the scp-1/CsCYP85A1 gene seemed active. The expression of CsCYP85A1 was higher in flowers than in the leaves and stem; its expression in the wild type was feedback regulated by brassinolide application. Its expression was reduced in C257 as compared with the wild type. This was the first report of map-based cloning of a plant height gene in cucurbit crops. The research highlighted the combined use of linkage mapping, an improved MutMap method and allelic diversity analysis in natural populations in quick cloning of simply inherited genes in cucumber. The roles of CsCYP85A1 in regulation of internode elongation in cucumber was discussed.

In this paper, the 3D model of the centrifugal compressor is established by Solidworks software at first. Second, the numerical simulation of the centrifugal compressor is carried out by using CFX software. Combined with the simulation results, the conclusion that properly reducing the outlet width of diffuser can effectively restrain the generation of flow separation and reduce the influence of impeller rotation on diffuser is revealed. Finally, the internal flow field structure and machine performance of the diffuser are improved. The research provides a reference for improving the performance and flow field structure of the compressor as well as the design of the vaneless diffuser.

In Arabidopsis (Arabidopsis thaliana), the UVR8-mediated signaling pathway is employed to attain UVB protection and acclimation to deal with low-dosage UVB (LDUVB)-induced stresses. Here, we identified SHORT HYPOCOTYL1 (SH1) in cucumber (Cucumis sativus), which regulates LDUVB-dependent hypocotyl elongation by modulating the UVR8 signaling pathway. We showed that hypocotyl elongation in cucumbers carrying the recessive sh1 allele was LDUVB insensitive and that Sh1 encoded a human SMARCA3-like chromatin remodeling factor. The allele frequency and distribution pattern at this locus among natural populations supported the wild cucumber origin of sh1 for local adaptation, which was under selection during domestication. The cultivated cucumber carries predominantly the Sh1 allele; the sh1 allele is nearly fixed in the semiwild Xishuangbanna cucumber, and the wild cucumber population is largely at Hardy-Weinberg equilibrium for the two alleles. The SH1 protein sequence was highly conserved among eukaryotic organisms, but its regulation of hypocotyl elongation in cucumber seems to be a novel function. While Sh1 expression was inhibited by LDUVB, its transcript abundance was highly correlated with hypocotyl elongation rate and the expression level of cell-elongation-related genes. Expression profiling of key regulators in the UVR8 signaling pathway revealed significant differential expression of CsHY5 between two near isogenic lines of Sh1. Sh1 and CsHY5 acted antagonistically at transcriptional level. A working model was proposed in which Sh1 regulates LDUVB-dependent hypocotyl elongation in cucumber through changing the chromatin states and thus the accessibility of CsHY5 in the UVR8 signaling pathway to promoters of LDUVB-responsive genes for hypocotyl elongation.

Immunoreactive (ir) staining of the neuropeptides oxytocin (OT) and vasopressin (AVP) was performed in the brains of Brandt’s voles (Lasiopodomys brandtii) and greater long-tailed hamsters (Tscherskia triton)—two species that differ remarkably in social behaviors. Social Brandt’s voles had higher densities of OT-ir cells in the medial preoptic area (MPOA) and medial amygdala (MeA) as well as higher densities of AVP-ir cells in the lateral hypothalamus (LH) compared to solitary greater long-tailed hamsters. In contrast, the hamsters had higher densities of OT-ir cells in the anterior hypothalamus (AH) and LH and higher densities of AVP-ir cells in the MPOA than the voles. OT-ir and AVP-ir fibers were also found in many forebrain areas with subtle species differences. Given the roles of OT and AVP in the regulation of social behaviors in other rodent species, our data support the hypothesis that species-specific patterns of central OT and AVP pathways may underlie species differences in social behaviors. However, despite a higher density of OT-ir cells in the paraventricular nucleus of the hypothalamus (PVN) in females than in males in both species, no other sex differences were found in OT-ir or AVP-ir staining. These data failed to support our prediction that a sexually dimorphic pattern of neuropeptide staining in the brain is more apparent in Brandt’s voles than in greater long-tailed hamsters.

Nb-B-Al-O nanocomposite films with different power of Al2O3 were successfully deposited on the Si substrate via multi-target magnetron co-sputtering method. The influences of Al2O3's content on structure and properties of obtained nanocomposite films through controlling Al2O3's power were investigated. Increasing the power of Al2O3 can influence the bombarding energy and cause the momentum transfer of NbB2. This can lead to the decreasing content of Al2O3. Furthermore, the whole films showed monocrystalline NbB2's (100) phase, and Al2O3 shaded from amorphous to weak cubic-crystalline when decreasing content of Al2O3. This structure and content changes were proof by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). When NbB2 grains were far from each other in lower power of Al2O3, the whole films showed a typical nanocomposite microstructure with crystalline NbB2 grains embedded in a matrix of an amorphous Al2O3 phase. Continuing increasing the power of Al2O3, the less content of Al2O3 tended to cause crystalline of cubic-Al2O3 between the close distances of different crystalline NbB2 grains. The appearance of cubic-crystallization Al2O3 can help to raise the nanocomposite films' mechanical properties to some extent. The maximum hardness and elastic modulus were up to 21.60 and 332.78 GPa, which were higher than the NbB2 and amorphous Al2O3 monolithic films. Furthermore, this structure change made the chemistry bond of O atom change from the existence of O-Nb, O-B, and O-Al bonds to single O-Al bond and increased the specific value of Al and O. It also influenced the hardness in higher temperature, which made the hardness variation of different Al2O3 content reduced. These results revealed that it can enhance the films' oxidation resistance properties and keep the mechanical properties at high temperature. The study highlighted the importance of controlling the Al2O3's content to prepare well-defined films with high mechanical properties and thermal stability.

A facile one-pot synthesis of N-(α-peroxy)indole and N-(α-peroxy)carbazole has been developed using metal-free, organo-acid-catalyzed three-component condensation reactions of indole/carbazole, aldehyde, and peroxide. Based on the reaction discovered, a new synthetic proposal for Fumitremorgin A and Verruculogen is introduced. Such a protocol could be easily handled and scaled up in an open atmosphere with a wide substrate scope, enabling the construction of a new molecule library.

Detection of 5005-bp LTR retrotransposon insertion found at the csgl3 allele in natural populations of cucumber. M: 1 kb markers; csgl3: the glabrous mutant RIL-46 M amplifies a 917 bp fragment suggesting presence of the insertion; 1 to 46: representative materials of the natural population (total 384) with 461 bp fragment showing no insertion of the LTR retrotransposon in these materials. (PPTX 138 kb)

Genomic DNA sequences for CsGL3 in wild type RIL-46 W (5188 bp) and csgl3 of the glabrous mutant RIL-46 M (10,199 bp). Target insert point was marked with green color. LTR retrotransposon sequence insertion in the mutant is underlined. (DOCX 19 kb)