Publications by authors named "Xianfeng Yi"

59 Publications

Genome-wide identification, phylogenetic, and expression analysis under abiotic stress conditions of LIM gene family in Medicago sativa L.

PLoS One 2021 30;16(6):e0252213. Epub 2021 Jun 30.

College of Resources and Environmental Sciences, Gansu Agricultural University, Lanzhou, China.

The LIM (Lin-11, Isl-1 and Mec-3 domains) family is a key transcription factor widely distributed in animals and plants. The LIM proteins in plants are involved in the regulation of a variety of biological processes, including cytoskeletal organization, the development of secondary cell walls, and cell differentiation. It has been identified and analyzed in many species. However, the systematic identification and analysis of the LIM genes family have not yet been reported in alfalfa (Medicago sativa L.). Based on the genome-wide data of alfalfa, a total of 21 LIM genes were identified and named MsLIM01-MsLIM21. Comprehensive analysis of the chromosome location, physicochemical properties of the protein, evolutionary relationship, conserved motifs, and responses to abiotic stresses of the LIM gene family in alfalfa using bioinformatics methods. The results showed that these MsLIM genes were distributed unequally on 21 of the 32 chromosomes in alfalfa. Gene duplication analysis showed that segmental duplications were the major contributors to the expansion of the alfalfa LIM family. Based on phylogenetic analyses, the LIM gene family of alfalfa can be divided into four subfamilies: αLIM subfamily, βLIM subfamily, γLIM subfamily, and δLIM subfamily, and approximately all the LIM genes within the same subfamily shared similar gene structure. The 21 MsLIM genes of alfalfa contain 10 Motifs, of which Motif1 and Motif3 are the conserved motifs shared by these genes. Furthermore, the analysis of cis-regulatory elements indicated that regulatory elements related to transcription, cell cycle, development, hormone, and stress response are abundant in the promoter sequence of MsLIM genes. Real-time quantitative PCR demonstrated that MsLIM gene expression is induced by low temperature and salt. The present study serves as a basic foundation for future functional studies on the alfalfa LIM family.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0252213PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8244919PMC
June 2021

Correction: Direct synthesis of the organic and Ge free Al containing BOG zeolite (ITQ-47) and its application for transformation of biomass derived molecules.

Chem Sci 2020 Nov 5;11(44):12221. Epub 2020 Nov 5.

Instituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas Avenida de los Naranjos s/n 46022 Valencia Spain

[This corrects the article DOI: 10.1039/D0SC04044D.].
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http://dx.doi.org/10.1039/d0sc90248aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8162468PMC
November 2020

Direct synthesis of the organic and Ge free Al containing BOG zeolite (ITQ-47) and its application for transformation of biomass derived molecules.

Chem Sci 2020 Oct 20;11(44):12103-12108. Epub 2020 Oct 20.

Instituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas Avenida de los Naranjos s/n 46022 Valencia Spain

Aluminosilicate boggsite (Si/Al-BOG) has been hydrothermally synthesized without adding organic structure-directing agents (OSDAs) in the synthesis gel using the borosilicogermanium ITQ-47 (Si/B-ITQ-47) zeolite as seeds. The introduction of the costly and environmentally less benign phosphazene organic structure-directing agent is not required to grow the zeolite. Physicochemical characterization experiments show that Si/Al-BOG has good crystallinity, high surface area, tetrahedral Al species, and acid sites. In order to test the catalytic performance of the zeolite, the synthesis of l,l-lactide from l-lactic acid was performed. Si/Al-BOG exhibits 88.2% conversion of l-lactic acid and 83.8% l,l-lactide selectivity, which are better than those of other zeolites studied up to now.
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http://dx.doi.org/10.1039/d0sc04044dDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8162478PMC
October 2020

Induced Active Sites by Adsorbate in Zeotype Materials.

J Am Chem Soc 2021 Jun 2;143(23):8761-8771. Epub 2021 Jun 2.

Wolfson Catalysis Centre, Department of Chemistry, University of Oxford, Oxford OX1 3QR, U.K.

There has been a long debate on how and where active sites are created for molecular adsorption and catalysis in zeolites, which underpin many important industrial applications. It is well accepted that Lewis acidic sites (LASs) and basic sites (LBSs) as active sites in pristine zeolites are generally believed to be the extra-framework Al species and residue anion (OH) species formed at fixed crystallographic positions after their synthesis. However, the dynamic interactions of adsorbates/reactants with pristine zeotype materials to "create" sites during real conditions remain largely unexplored. Herein, direct experimental observation of the establishment of induced active sites in silicoaluminophosphate (SAPO) by an adsorbate is made, which contradicts the traditional view of the fixed active sites in zeotype materials. Evidence shows that an induced frustrated Lewis pair (FLP, three-coordinated framework as LAS and Si (H) as LBS) can be transiently favored for heterolytic molecular binding/reactions of competitive polar adsorbates due to their ineffective orbital overlap in the rigid framework. High-resolution magic-angle-spinning solid-state NMR, synchrotron X-ray diffraction, neutron powder diffraction, diffuse reflectance infrared Fourier transform spectroscopy, and molecular dynamics demonstrate the transformation of a typical Brønsted acid site (Al(OH)Si) in SAPO zeolites to new induced FLP structure for hetereolytic binding upon adsorption of a strong polar adsorbate. Our unprecedented finding opens up a new avenue to understanding the dynamic establishment of active sites for adsorption or chemical reactions under molecular bombardment of zeolitic structures.
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http://dx.doi.org/10.1021/jacs.1c03166DOI Listing
June 2021

Thermal resistance effect on anomalous diffusion of molecules under confinement.

Proc Natl Acad Sci U S A 2021 May;118(21)

State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, 430071 Wuhan, China;

Diffusion is generally faster at higher temperatures. Here, a counterintuitive behavior is observed in that the movement of long-chain molecules slows as the temperature increases under confinement. This report confirms that this anomalous diffusion is caused by the "thermal resistance effect," in which the diffusion resistance of linear-chain molecules is equivalent to that with branched-chain configurations at high temperature. It then restrains the molecular transportation in the nanoscale channels, as further confirmed by zero length column experiments. This work enriches our understanding of the anomalous diffusion family and provides fundamental insights into the mechanism inside confined systems.
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http://dx.doi.org/10.1073/pnas.2102097118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8166051PMC
May 2021

Tracking Animal-Dispersed Seedlings Using N Xylem Injection Method.

Front Plant Sci 2021 30;12:582530. Epub 2021 Apr 30.

College of Life Sciences, Qufu Normal University, Qufu, China.

Although various seed-marking methods have been developed for seed dispersal, it remains difficult to track the actual patterns of seed dispersal and seedling recruitment. Thus, new labeling methods that accurately track seedling establishment along with seed movement would help us better understand seed dispersal. Here, we developed a new nondestructive method using N xylem injection to track seed dispersal and seedling recruitment based on the enriched isotopic signals in the mature seeds. Our results first showed that xylem injection of N successfully enriched N both in the acorns and seedlings of . By marking acorns and seedlings with N stable isotopes, we successfully tracked seedlings established from acorns dispersed by seed-eating animals in the field. Our xylem N injection caused little alteration to seeds and showed no significant effects on seed selection by seed-eating animals as well as seed germination and seedling establishment, verifying the validity of the N xylem injection method to track seedling establishment. Our xylem N injection method is expected to be a powerful tool for tracking seed dispersal and seedling recruitment mediated by seed-eating animals in seed dispersal ecology.
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http://dx.doi.org/10.3389/fpls.2021.582530DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8120291PMC
April 2021

Electronic-State Manipulation of Surface Titanium Activates Dephosphorylation Over TiO Near Room Temperature.

Angew Chem Int Ed Engl 2021 07 14;60(29):16149-16155. Epub 2021 Jun 14.

Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China.

Dephosphorylation that removes a phosphate group from substrates is an important reaction for living organisms and environmental protection. Although CeO has been shown to catalyze this reaction, cerium is low in natural abundance and has a narrow global distribution (>90 % of these reserves are located within six countries). It is thus imperative to find another element/material with high worldwide abundance that can also efficiently extract the phosphate out of agricultural waste for phosphorus recycle. Using para-nitrophenyl phosphate (p-NPP) as a model compound, we demonstrate that TiO with a F-modified (001) surface can activate p-NPP dephosphorylation at temperatures as low as 40 °C. By probe-assisted nuclear magnetic resonance (NMR), it was revealed that the strong electron-withdrawing effect of fluorine makes Ti atoms (the active sites) on the (001) surface very acidic. The bidentate adsorption of p-NPP on this surface further promotes its subsequent activation with a barrier ≈20 kJ mol lower than that of the pristine (001) and (101) surfaces, allowing the activation of this reaction near room temperature (from >80 °C).
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http://dx.doi.org/10.1002/anie.202104397DOI Listing
July 2021

Gating control effect facilitates excellent gas selectivity in a novel Na-SSZ-27 zeolite.

Chem Commun (Camb) 2021 Apr;57(34):4170-4173

State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, P. R. China.

A novel Na-SSZ-27 zeolite was demonstrated to possess excellent H2/CO2 diffusion selectivity of more than 100. This investigation highlights the crucial effect of the "gating control" of the 8-ring windows on the separation, where sodium cations act as gates to selectively control the diffusion of CO2 and promote the selectivity for H2.
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http://dx.doi.org/10.1039/d1cc00164gDOI Listing
April 2021

Surface Fingerprinting of Faceted Metal Oxides and Porous Zeolite Catalysts by Probe-Assisted Solid-State NMR Approaches.

Acc Chem Res 2021 05 15;54(10):2421-2433. Epub 2021 Apr 15.

State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China.

Acid catalysis in heterogeneous systems such as metal oxides and porous zeolites has been widely involved in various catalytic processes for chemical and petrochemical industries. In acid-catalyzed reactions, the performance (e.g., activity and selectivity) is closely associated with the acidic features of the catalysts, viz., type (Lewis vs Brønsted acidity), distribution (external vs internal surface), strength (strong vs weak), concentration (amount), and spatial interactions of acidic sites. The characterization of local structure and acidic properties of these active sites has important implications for understanding the reaction mechanism and the practical catalytic applications of acidic catalysts. Among diverse acidity characterization approaches, the solid-state nuclear magnetic resonance (SSNMR) technique with suitable probe molecules has been recognized as a reliable and versatile tool. Such a probe-assisted SSNMR approach could provide qualitative (type, distribution, and spatial interactions) and quantitative (strength and concentration) information on each acidic site. This Account aims to integrate our recent important findings in determining the structures and acidic characteristics of some typical metal oxide and zeolite catalysts by using the probe-assisted SSNMR technique, as well as clarifying the continuously evolving process of each discrete acidic site under hydrothermal or chemical treatments even at the molecular level with multiscale theoretical simulations.More specifically, we will describe herein the development and applications of the probe-assisted SSNMR methods, such as trimethylphosphine (TMP) and acetonitrile- (CDCN) in conjunction with advanced two-dimensional (2D) homo- and heteronuclear correlation spectroscopy, for characterizing the structures and properties of acidic sites in varied solid catalysts. Moreover, relevant information regarding the surface fingerprinting of various facets on crystalline metal oxide nanoparticles and active centers inside porous zeolites, the mapping of relevant spatial interactions, and the verification of structure-activity correlation were investigated as well. Relevant discussions are mainly based on the recent NMR experiments of our collaborating research groups, including (i) determining the acidic characterization with probe-assisted SSNMR approaches, (ii) mapping various active centers (or crystalline facets), and (iii) revealing their influence on catalytic performance of solid acid catalyst systems. It is anticipated that this information may provide more in-depth insights toward our fundamental understanding of solid acid catalysis.
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http://dx.doi.org/10.1021/acs.accounts.1c00069DOI Listing
May 2021

Isolated boron in zeolite for oxidative dehydrogenation of propane.

Science 2021 04;372(6537):76-80

Key Lab of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China.

Oxidative dehydrogenation of propane (ODHP) is a key technology for producing propene from shale gas, but conventional metal oxide catalysts are prone to overoxidation to form valueless CO Boron-based catalysts were recently found to be selective for this reaction, and B-O-B oligomers are generally regarded as active centers. We show here that the isolated boron in a zeolite framework without such oligomers exhibits high activity and selectivity for ODHP, which also hinders full hydrolysis for boron leaching in a humid atmosphere because of the B-O-SiO linkage, achieving superior durability in a long-period test. Furthermore, we demonstrate an isolated boron with a -B[OH…O(H)-Si] structure in borosilicate zeolite as the active center, which enables the activation of oxygen and a carbon-hydrogen bond to catalyze the ODHP.
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http://dx.doi.org/10.1126/science.abe7935DOI Listing
April 2021

Synergistically enhance confined diffusion by continuum intersecting channels in zeolites.

Sci Adv 2021 Mar 12;7(11). Epub 2021 Mar 12.

State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, and Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China.

In separation and catalysis applications, adsorption and diffusion are normally considered mutually exclusive. That is, rapid diffusion is generally accompanied by weak adsorption and vice versa. In this work, we analyze the anomalous loading-dependent mechanism of -xylene diffusion in a newly developed zeolite called SCM-15. The obtained results demonstrate that the unique system of "continuum intersecting channels" (i.e., channels made of fused cavities) plays a key role in the diffusion process for the molecule-selective pathways. At low pressure, the presence of strong adsorption sites and intersections that provide space for molecule rotation facilitates the diffusion of -xylene along the direction. Upon increasing the molecular uptake, the adsorbates move faster along the direction because of the effect of continuum intersections in reducing the diffusion barriers and thus maintaining the large diffusion coefficient of the diffusing compound. This mechanism synergistically improves the diffusion in zeolites with continuum intersecting channels.
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http://dx.doi.org/10.1126/sciadv.abf0775DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7954456PMC
March 2021

In Situ Observation of Non-Classical 2-Norbornyl Cation in Confined Zeolites at Ambient Temperature.

Angew Chem Int Ed Engl 2021 Feb 28;60(9):4581-4587. Epub 2021 Jan 28.

State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, P. R. China.

Carbonium ions are an important class of reaction intermediates, but their dynamic evolution is difficult to be monitored by in situ techniques under experimental conditions because of their extremely short lifetime. Probably the most famous case is 2-norbornyl cation (2NB ): its existing form (classical or non-classical) had been debated for decades, until the concrete proof of non-classical geometry was achieved by X-ray crystallographic characterization at ultra-low temperature (40 K) and super acidic environment. However, we lack the understanding about 2NB at ambient conditions. Herein, by taking advantage of the confinement effect and delocalized acidic environment of zeolites, we successfully stabilized 2NB and unequivocally confirmed its "non-classical" structure inside the ZSM-5 zeolite by ab initio molecular dynamics simulations and C solid-state nuclear magnetic resonance experiments. It is the first time to in situ observe the non-classical 2NB without the super acidic environment at ambient temperature, which provides a new strategy to expand the carbocation chemistry.
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http://dx.doi.org/10.1002/anie.202013384DOI Listing
February 2021

Inter-trophic Interaction of Gut Microbiota in a Tripartite System.

Microb Ecol 2021 May 14;81(4):1075-1087. Epub 2020 Nov 14.

College of Life Sciences, Qufu Normal University, Qufu, 273165, China.

Gut microbiota can be transmitted either environmentally or socially and vertically at intraspecific level; however, whether gut microbiota interact along trophic levels has been largely overlooked. Here, we characterized the gut bacterial communities of weevil larvae of Curculio arakawai that infest acorns of Mongolian oak (Quercus mongolica) as well as acorn-eating mammals, Siberian chipmunk (Tamias sibiricus), to test whether consumption of seed-borne larvae remodels the gut bacterial communities of T. sibiricus. Ingestion of weevil larvae of C. arakawai significantly altered the gut bacterial communities of T. sibiricus. Consequently, T. sibiricus fed larvae of C. arakawai showed higher capability to counter the negative effects of tannins, in terms of body weight maintenance, acorn consumption, N content in feces, urine pH, and blood ALT activity. Our results may first show that seed-borne insects as hidden players have a potential to alter the gut microbiota of seed predators in the tripartite system.
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http://dx.doi.org/10.1007/s00248-020-01640-4DOI Listing
May 2021

Olfaction alters spatial memory strategy of scatter-hoarding animals.

Integr Zool 2021 Jan 22;16(1):128-135. Epub 2020 Nov 22.

College of Life Sciences, Qufu Normal University, Qufu, China.

Although it has been suggested that olfaction is closely interconnected with hippocampal systems, whether olfaction regulates spatial memory strategy remains never known. Furthermore, no study has examined how olfaction mediates spatial memory established on the external objects, for example, caches made by scatter-hoarding animals. Here, we experimentally induced nondestructive and reversible olfaction loss of a scatter-hoarding animal Leopoldamys edwardsi, to test whether and how olfaction regulates spatial memory to mediate cache recovery and pilferage. Our results showed that the normal L. edwardsi preferred to pilfer caches of others rather than to recover their own using accurate spatial memory (35.7% vs. 18.6%). Anosmic L. edwardsi preferred to recover the caches they made prior to olfaction loss rather than to pilfer from others relied on spatial memory (54.2% vs. 36.0%). However, L. edwardsi with anosmia showed no preference either to the caches they established after olfaction loss or caches made by others (25.8% vs. 29.1%). These collectively indicate that olfaction loss has a potential to affect new memory formation but not previously established spatial memory on caches. Our study first showed that olfaction modified spatial memory strategy in cache recovery and pilferage behaviors of scatter-hoarding animals. We suggest that future studies pay more attention to the evolution of olfaction and its relationship with spatial memory strategy.
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http://dx.doi.org/10.1111/1749-4877.12498DOI Listing
January 2021

The elephant grass (Cenchrus purpureus) genome provides insights into anthocyanidin accumulation and fast growth.

Mol Ecol Resour 2021 Feb 28;21(2):526-542. Epub 2020 Oct 28.

State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China.

Elephant grass (2n = 4x = 28; Cenchrus purpureus Schumach.), also known as Napier grass, is an important forage grass and potential energy crop in tropical and subtropical regions of Asia, Africa and America. However, no study has yet reported a genome assembly for elephant grass at the chromosome scale. Here, we report a high-quality chromosome-scale genome of elephant grass with a total size of 1.97 Gb and a 1.5% heterozygosity rate, obtained using short-read sequencing, single-molecule long-read sequencing and Hi-C chromosome conformation capture. Evolutionary analysis showed that subgenome A' of elephant grass and pearl millet may have originated from a common ancestor more than 3.22 million years ago (MYA). Further, allotetraploid formation occurred at approximately 6.61 MYA. Syntenic analyses within elephant grass and with other grass species indicated that elephant grass has experienced chromosomal rearrangements. We found that some key enzyme-encoding gene families related to the biosynthesis of anthocyanidins and flavonoids were expanded and highly expressed in leaves, which probably drives the production of these major anthocyanidin compounds and explains why this elephant grass cultivar has a high anthocyanidin content. In addition, we found a high copy number and transcript levels of genes involved in C photosynthesis and hormone signal transduction pathways that may contribute to the fast growth of elephant grass. The availability of elephant grass genome data advances our knowledge of the genetic evolution of elephant grass and will contribute to further biological research and breeding as well as for other polyploid plants in the genus Cenchrus.
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http://dx.doi.org/10.1111/1755-0998.13271DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7821259PMC
February 2021

Solid-state P NMR mapping of active centers and relevant spatial correlations in solid acid catalysts.

Nat Protoc 2020 10 23;15(10):3527-3555. Epub 2020 Sep 23.

State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, P. R. China.

Solid acid catalysts are used extensively in various advanced chemical and petrochemical processes. Their catalytic performance (namely, activity, selectivity, and reaction pathway) mostly depends on their acid properties, such as type (Brønsted versus Lewis), location, concentration, and strength, as well as the spatial correlations of their acid sites. Among the diverse methods available for acidity characterization, solid-state nuclear magnetic resonance (SSNMR) techniques have been recognized as the most valuable and reliable tool, especially in conjunction with suitable probe molecules that possess observable nuclei with desirable properties. Taking P probe molecules as an example, both trimethylphosphine (TMP) and trimethylphosphine oxide (TMPO) adsorb preferentially to the acid sites on solid catalysts and thus are capable of providing qualitative and quantitative information for both Brønsted and Lewis acid sites. This protocol describes procedures for (i) the pretreatment of typical solid acid catalysts, (ii) adoption and adsorption of various P probe molecules, (iii) considerations for one- and two-dimensional (1D and 2D, respectively) NMR acquisition, (iv) relevant data analysis and spectral assignment, and (v) methodology for NMR mapping with the assistance of theoretical calculations. Users familiar with SSNMR experiments can complete P-H heteronuclear correlation (HETCOR), P-P proton-driven spin diffusion (PDSD), and double-quantum (DQ) homonuclear correlation with this protocol within 2-3 d, depending on the complexity and the accessible acid sites of the solid acid samples.
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http://dx.doi.org/10.1038/s41596-020-0385-6DOI Listing
October 2020

Radicle pruning by seed-eating animals helps oak seedlings absorb more soil nutrient.

Integr Zool 2020 Sep 15. Epub 2020 Sep 15.

College of Life Sciences, Qufu Normal University, Qufu, China.

Although radicle pruning has well been observed in plant-animal interactions, research has not been conducted to determine how radicle pruning by seed-eating animals regulates nutrition mobilization of cotyledonary reserves and absorption of soil nutrients. We used stable nitrogen isotopes to test how acorns of early-germinating oak species (Quercus variabilis, Q. aliena, and Q. mogolica) trade off nutrients in the cotyledons and those in the soil in response to radicle pruning by seed-eating rodents. Radicle pruning by rodents resulted in root branching in the 3 early-germinating oak species. Moreover, radicle pruning increased shoot dry weight and substantially reduced the root-to-shoot ratio of oak species. Corresponding to the decreased dry weight of roots and root-to-shoot ratio, the dry weight of the remnant cotyledons was higher after radicle pruning in the 3 oak species. We provided first evidence that radicle pruning by seed-eating animals improved seedling performance of early-germinating oaks by increasing absorption of nutrients from soil. The results indicate that early-germinating oak seedlings trade off nutrition budget by altering nutrient absorption from soil and reserve mobilization from cotyledons in response to radicle pruning by seed-eating animals. Our study provided new insight into the nutrition allocation mechanism of young seedlings in response to radicle pruning by seed-eating animals, reflecting a mutualistic interaction between early-germinating oak and food-hoarding animals.
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http://dx.doi.org/10.1111/1749-4877.12489DOI Listing
September 2020

Effects of masting on seedling establishment of a rodent-dispersed tree species in a warm-temperate region, northern China.

Integr Zool 2021 Jan 30;16(1):97-108. Epub 2020 May 30.

State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, Chinese Academy of Sciences, Institute of Zoology, Beijing, China.

Masting is an evolutionary strategy used by plants to promote seed survival and/or seed dispersal under animal predation, but its effects on seedling establishment in field condition are rarely tested by long-term experiments incorporating combined effects of seed and animal abundance. Here, we tracked seed production, rodent-mediated seed dispersal, and seedling establishment in Armeniaca sibirica from 2005 to 2014 in a warm-temperate forest in northern China, and examined the effects of seed abundance and per capita seed availability on seed fate and seedling recruitment rate. Our results showed that seed abundance or per capita seed availability generally benefited the seedling recruitment of A. sibirica through increasing dispersal intensity, supporting predator dispersal hypothesis. However, seedling recruitment showed satiated or even dome-shaped association with per capita seed availability, suggesting the benefit to trees would be decreased when seed abundance were too high as compared to rodent abundance (a satiated effect). Our results suggest that the predator dispersal and satiation effects of masting on seedling recruitment can operate together in one system and conditionally change with seed and animal abundance.
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http://dx.doi.org/10.1111/1749-4877.12450DOI Listing
January 2021

Modulation of Self-Separating Molecular Catalysts for Highly Efficient Biomass Transformations.

Chemistry 2020 Sep 13;26(51):11900-11908. Epub 2020 Aug 13.

State Key Laboratory of Chemical Resource Engineering, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P.R. China.

The energetically viable fabrication of stable and highly efficient solid acid catalysts is one of the key steps in large-scale transformation processes of biomass resources. Herein, the covalent modification of the classical Dawson polyoxometalate (POMs) with sulfonic acids (-SO H) is reported by grafting sulfonic acid groups on the POM's surface followed by oxidation of (3-mercaptopropyl)trimethoxysilane. The acidity of TBA -P W -SO H (TBA=tetrabutyl ammonium) has been demonstrated by using P NMR spectroscopy, clearly indicating the presence of strong Brønsted acid sites. The presence of TBA counterions renders the solid acid catalyst as a promising candidate for phase transfer catalytic processes. The TBA -P W -SO H shows remarkable activity and selectivity, excellent stability, and great substrate compatibility for the esterification of free fatty acids (FFA) with methanol and conversion into biodiesel at 70 °C with >98 % conversion of oleic acid in 20 min. The excellent catalytic performance can be attributed to the formation of a catalytically active emulsion, which results in a uniform catalytic behavior during the reaction, leading to efficient interaction between the substrate and the active sites of the catalyst. Most importantly, the catalyst can be easily recovered and reused without any loss of its catalytic activity owing to its excellent phase transfer properties. This work offers an efficient and cost-effective strategy for large-scale biomass conversion applications.
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http://dx.doi.org/10.1002/chem.202001451DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7540606PMC
September 2020

Exclusion of interspecific competition reduces scatter-hoarding of Siberian chipmunk Tamias sibiricus: A field study.

Integr Zool 2020 Mar;15(2):127-134

College of Life Sciences, Jiangxi Normal University, Nanchang, China.

Although food availability and the abundance of seed predators have been postulated to affect seed dispersal, it is not clear how seed-eating animals modify their scatter-hoarding strategies in response to different levels of interspecific competition. We placed paired germinated and ungerminated acorns of Quercus mongolica on 30-cm high platforms to exclude potential interspecific competition of the predominant larder hoarders Apodemus peninsulae and Myodes rufocanus, to investigate seed dispersal by a predominant scatter-hoarder, Tamias sibiricus, in the field in north-eastern China. Our results showed that T. sibiricus ate more acorns in situ in the absence of interspecific competition. In the presence of interspecific competition of A. peninsulae and C. rufocanus, however, more acorns were scatter-hoarded by T. sibiricus. Regardless of interspecific competition, germination of acorns showed no significant effects on seed dispersal patterns, inconsistent with the "seed perishability hypothesis" that animals avoid hoarding seeds with high perishability. Exclusion of interspecific competition, though relatively increasing the per capita seed abundance, appears to reduce seed dispersal, scatter-hoarding and seedling establishment. Therefore, we propose that moderate interspecific competition rather than competition exclusion may benefit seed scatter-hoarding and seedling establishment.
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http://dx.doi.org/10.1111/1749-4877.12416DOI Listing
March 2020

One acorn produces two seedlings in Chinese cork oak .

Plant Signal Behav 2019 22;14(10):e1654817. Epub 2019 Aug 22.

College of Life Sciences, Qufu Normal University , Qufu , China.

Although the early germination of white oaks has long been considered an adaptation to counter animal predation, the role of the robust radicles of white oak acorns has been largely neglected in the interaction between acorns and seed-eating animals. Here, the regeneration capabilities of the pruned radicles of intermediate oak left by the acorn-eating animals were compared to test the 'one acorn produce two seedlings' hypothesis stating that the remnant radicles exhibit the capability to produce normal seedlings owning to their atypical nutritional and anatomical characteristics. Our results first showed that both pruned radicle and cotyledons from single acorn successfully established seedlings, providing strong evidence on an old puzzle that the robust radicles of early-germinating oak acorns act as reserved propagules, allowing them to escape animals' predation. Our study also suggests that much of the investment in the food reserves of an acorn may be important as a food reward for the animals that disperse the acorns, rather than simply serving as energy for the young seedling.
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http://dx.doi.org/10.1080/15592324.2019.1654817DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6768198PMC
June 2020

Developing two-dimensional solid superacids with enhanced mass transport, extremely high acid strength and superior catalytic performance.

Chem Sci 2019 Jun 30;10(23):5875-5883. Epub 2019 May 30.

Wuhan Center for Magnetic Resonance , Key Laboratory of Magnetic Resonance in Biological Systems , State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics , Wuhan Institute of Physics and Mathematics , Chinese Academy of Sciences , Wuhan 430071 , China . Email:

Solid acids have been widely used as heterogeneous catalysts in developing green and sustainable chemistry. However, it remains a challenge to improve the mass transport properties and acid strength of solid acids simultaneously. Herein, we report a class of two dimensional (2D) layered hybrid solid acids with outstanding mass transfer and extremely high acid strength by incorporating sulfonated polymers in-between montmorillonite layers. The 2D layered structure and broad distribution of pore sizes allow for highly efficient mass transport of substrate molecules into and out of the solid acids. The acid strength of these solid acids was found to be stronger than that of 100% HSO, HPWO and any other reported solid acids to date, as determined by H and P solid-state NMR. These 2D solid acids show extraordinary catalytic performance in biomass conversion to fuels, superior to that of HPWO, HCl and HSO. Theoretical calculations and control experiments reveal that H-bond based interactions between the polymer and montmorillonite facilitate the unusually high acid strengths found in these samples.
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http://dx.doi.org/10.1039/c9sc01988jDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6582756PMC
June 2019

Rodent-Mediated Seed Dispersal Shapes Species Composition and Recruitment Dynamics in Ecotones.

Front Plant Sci 2018 20;9:1911. Epub 2018 Dec 20.

College of Life Sciences, Henan Normal University, Xinxiang, China.

Ecotones are considered unique environments, and the concepts of edge effects and ecotonal species have been applied widely. Our understanding of the mechanisms that underlie population and community responses to edge effects has been advanced by recent studies. However, little evidence exists to support an increased density and species richness in ecotones regarding rodent-mediated seed dispersal in response to edge plots between communities. and communities are typical of the Qinling Mountains, China. To elucidate what shapes tree species composition and recruitment dynamics in ecotones, we compared the differences in secondary and tertiary seed dispersal as well as predation in pine and oak by scatter-hoarding rodents as well as the regeneration characteristics of both species in their ecotones with different plots (i.e., 5-8, 15-18, and 27-30 m widths) in the eastern Qinling Mountains. We found that the seeds of pine and oak were removed rapidly, with no differences in the seed removal rates in their ecotones with different plots. Moreover, 13.0 and 36.0% of the scatter hoards of pine and oak, respectively, were established by small rodents in ecotones with a width of 5-8 m, and 3.67 and 7.33% in ecotones with a width of 27-30 m. The seedling densities of pine and oak were significantly higher in ecotones at widths of 5-8 m compared with widths of 15-18 and 27-30 m. According to the seed dispersal and seedling recruitment patterns of pine and oak, the disproportionate abundance of seedlings in ecotones may be due at least partly to patterns of seed caching by rodents.
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http://dx.doi.org/10.3389/fpls.2018.01911DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6308137PMC
December 2018

Visual and auditory cues facilitate cache pilferage of Siberian chipmunks (Tamias sibiricus) under indoor conditions.

Integr Zool 2019 Jul;14(4):354-365

Institute of Ecology and Evolution, School of Life Sciences, Central China Normal University, Wuhan, China.

In the struggle for survival, scatter-hoarding rodents are known to cache food and pilfer the caches of others. The extent to which rodents utilize auditory/visual cues from conspecifics to improve cache-pilfering is unknown. Here, Siberian chipmunks (Tamias sibiricus) were allowed to search for caches of Corylus heterophylla seeds (man-made caches and animal-made caches) after experiencing cues from a conspecific's cache-searching events. For each type of cache, 3 experimental scenarios were presented: (1) alone (control); (2) auditory/visual (hearing and seeing conspecific's cache-searching events); and (3) auditory only (hearing conspecific's cache-searching events only) with random orders. The subjects located man-made caches faster, harvested more caches, and hoarded more seeds both in the auditory/visual and the auditory only treatments compared to the control, while scatter-hoarding more seeds in the auditory/visual treatment but larder-hoarding more seeds in the auditory only treatment. Compared to the control, the animals spent less time locating animal-made caches, harvested more caches, ate fewer seeds, larder-hoarded more seeds and hoarded more seeds in total both in the auditory/visual and the auditory only treatments, while eating more seeds and hoarded fewer seeds in total in the auditory only treatment than in the auditory/visual treatment. The results also show that females spent less time locating the animal-made caches, but they scatter-hoarded fewer seeds than males in the auditory/visual treatment. To the best of our knowledge, this is the first report that visual and/or auditory cues of conspecifics improve cache-pilfering and hoarding in rodents.
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http://dx.doi.org/10.1111/1749-4877.12373DOI Listing
July 2019

A nonpolar solvent effect by CH/π interaction inside zeolites: characterization, mechanism and concept.

Chem Commun (Camb) 2018 Nov;54(95):13435-13438

State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China.

The acidity enhancement induced by the nonpolar solvent effect of naphthalene inside zeolites was unambiguously identified. The mechanism of such an effect due to the CH/π interaction in the nonpolar environment has been revealed based on the advanced 2D 1H-13C correlation NMR technique and DFT calculations for the first time.
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http://dx.doi.org/10.1039/c8cc08310jDOI Listing
November 2018

To Be or Not To Be Protonated: cyclo-N in Crystal and Solvent.

J Phys Chem Lett 2018 Dec 13;9(24):7137-7145. Epub 2018 Dec 13.

State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan , Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences , Wuhan 430071 , P.R. China.

Pentazole (HN) and its anion ( cyclo-N) have been elusive for nearly a century because of the unstable N ring. Recently, Zhang et al. reported the first synthesis and characterization of the pentazolate anion cyclo-N in (N)(HO)(NH)Cl salt at ambient conditions ( Science 2017, 355, 374 ). However, whether the cyclo-N in (N)(HO)(NH)Cl salt is protonated or not has been debated ( Huang and Xu, Science, 2018, 359, eaao3672 ; Jiang et al. Science, 2018, 359, aas8953 ). Herein, we employed ab initio molecular dynamics (AIMD) simulations, which can well present the dynamic behavior at realistic experimental conditions, to examine the potential protonated state of cyclo-N in both crystal and dimethyl sulfoxide (DMSO) solvent. Our simulations revealed that the protonation reaction of (N)(HO)(NH)Cl → (N)(NH)(HO)(HO)(NH)Cl is thermodynamically spontaneous according to Δ G < 0, and the small energy barrier of 12.6 kJ/mol is not enough to prevent the partial protonation of cyclo-N due to the temperature effect; consequently, both deprotonated and protonated cyclo-N exist in the crystal. In comparison, the DMSO solvent effect can remarkably reduce the difference of proton affinities among cyclo-N, HO, and NH, and the temperature effect can finally break these hydrogen bonds and lead to the deprotonated cyclo-N in DMSO solvent. Our AIMD simulations reconcile the recent controversy.
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http://dx.doi.org/10.1021/acs.jpclett.8b02841DOI Listing
December 2018

Brønsted/Lewis acid sites synergistically promote the initial C-C bond formation in the MTO reaction.

Chem Sci 2018 Aug 27;9(31):6470-6479. Epub 2018 Jun 27.

State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics , National Center for Magnetic Resonance in Wuhan , Key Laboratory of Magnetic Resonance in Biological Systems , Wuhan Institute of Physics and Mathematics , Chinese Academy of Sciences , Wuhan 430071 , P. R. China . Email:

The methanol-to-olefin (MTO) reaction is an active field of research due to conflicting mechanistic proposals for the initial carbon-carbon (C-C) bond formation. Herein, a new methane-formaldehyde pathway, a Lewis acid site combined with a Brønsted acid site in zeolite catalysts can readily activate dimethyl ether (DME) to form ethene, is identified theoretically. The mechanism involves a hydride transfer from Al-OCH on the Lewis acid site to the methyl group of the protonated methanol molecule on the adjacent Brønsted acid site leading to synchronous formation of methane and Al-COH (which can be considered as formaldehyde (HCHO) adsorbed on the Al Lewis acid sites). The strong electrophilic character of the Al-COH intermediate can strongly accelerate the C-C bond formation with CH, as indicated by the significant decrease of activation barriers in the rate-determining-step of the catalytic processes. These results highlight a synergy of extra-framework aluminum (EFAl) Lewis and Brønsted sites in zeolite catalysts that facilitates initial C-C bond formation in the initiation step of the MTO reaction the Al-COH intermediate.
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http://dx.doi.org/10.1039/c8sc02302fDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6115684PMC
August 2018

Analysis of miRNAs and their target genes in five Melilotus albus NILs with different coumarin content.

Sci Rep 2018 09 20;8(1):14138. Epub 2018 Sep 20.

State Key Laboratory of Grassland Agro-ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, P.R. China.

MicroRNAs (miRNAs) exhibit diverse and important roles in regulation of various biological processes at the post-transcriptional level in plants. In this study, Melilotus albus miRNA and their target genes were elucidated from five M. albus near-isogenic lines which differ in coumarin content to construct small RNA libraries through high-throughput sequencing. A total of 417 known miRNAs and 76 novel miRNAs were identified in M. albus. In addition, 4155 different target genes for 114 known miRNA families and 14 target genes for 2 novel miRNAs were identified in M. albus. Moreover, mtr-miR5248 and mtr-miR7701-5p target c35498_g3 and gma-miR396a-3p target c37211_g1 involved in coumarin biosynthesis were identified by using the differential expression of the miRNAs and their target genes correlation analysis. The abundance of miRNAs and potential target genes were validated by qRT-PCR analysis. We also found that there were both positive and negative expression changing patterns between miRNAs and their related target genes. Our first and preliminary study of miRNAs will contribute to our understanding of the functions and molecular regulatory mechanisms of miRNAs and their target genes, and provide information on regulating the complex coumarin pathway in M. albus for future research.
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http://dx.doi.org/10.1038/s41598-018-32153-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6147922PMC
September 2018

Origin and Structural Characteristics of Tri-coordinated Extra-framework Aluminum Species in Dealuminated Zeolites.

J Am Chem Soc 2018 08 17;140(34):10764-10774. Epub 2018 Aug 17.

State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics , Chinese Academy of Sciences , Wuhan 430071 , P. R. China.

Post-synthetic dealumination treatment is a common tactic adopted to improve the catalytic performance of industrialized zeolitic catalysts through enhancements in acidity and stability. However, among the possible extra-framework aluminum (EFAL) species in dealuminated zeolites such as Al, Al(OH), Al(OH), AlO, AlOOH, and Al(OH), the presence of tri-coordinated EFAL-Al species, which exhibit large quadrupolar effect due to the lack of hydrogen-bonding species, was normally undetectable by conventional one- and two-dimensional H and/or Al solid-state nuclear magnetic resonance (SSNMR) techniques. By combining density functional theory (DFT) calculations with experimental P SSNMR using trimethylphosphine (TMP) as the probe molecule, we report herein a comprehensive study to certify the origin, fine structure, and possible location of tri-coordinated EFAL-Al species in dealuminated HY zeolite. The spatial proximities and synergies between the Brønsted and various Lewis acid sites were clearly identified, and the origin for the observed EFAL-Al species with ultra-strong Lewis acidity was deduced to be at the expense of adjacent Brønsted acid sites. The excellent performance of such tri-coordinated EFAL species was furthermore confirmed by glucose isomerization reactions.
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http://dx.doi.org/10.1021/jacs.8b04819DOI Listing
August 2018

A Molecular Ferroelectric Showing Room-Temperature Record-Fast Switching of Spontaneous Polarization.

Angew Chem Int Ed Engl 2018 Jul 9;57(31):9833-9837. Epub 2018 Jul 9.

State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002, China.

Fast switching of spontaneous polarization (P ) is one of the most essential requirements for ferroelectrics used in the field of data storage. However, in contrast to inorganic counterparts, the low operating frequency (<500 Hz) for molecular ferroelectrics severely hinders their large-scale applications. Herein, for the first time, we achieved the room-temperature fastest switching of the P in a new molecular ferroelectric, N-methylmorpholinium trinitrophenolate (1), which displays notable ferroelectricity (P =3.2 μc cm ). Strikingly, electric polarizations of 1 have been switched under a record-high frequency of 263 kHz, and this performance remains stable without any obvious fatigue after ca. 2×10 switching cycles. To our knowledge, 1 is the first organic ferroelectric to switch polarization at such a high operating frequency, exceeding the majority of organic ferroelectrics, which opens up new possibilities for its potential in the field of non-volatile memory.
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http://dx.doi.org/10.1002/anie.201805776DOI Listing
July 2018