Publications by authors named "Haodong Liu"

45 Publications

Neuroanatomy of melanocortin-4 receptor pathway in the mouse brain.

Open Life Sci 2020 13;15(1):580-587. Epub 2020 Aug 13.

College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China.

Objective: Melanocortin-4 receptors (MC4Rs) are key regulators of energy homeostasis and adipose deposition in the central nervous system. Considering that MC4R expression regions and function-related research mainly focus on the paraventricular nucleus (PVN), little is known about their distribution throughout the mouse brain, although its messenger RNA distribution has been analyzed in the rat. Therefore, MC4R protein localization in mouse neurons was the focus of this study.

Methods: MC4R protein distribution was assessed in mice through immunofluorescence and Western blotting.

Results: MC4R was differentially expressed throughout the arcuate nucleus (ARC), nucleus of the solitary tract (NTS), raphe pallidus (RPa), medial cerebellar nucleus, intermediolateral nucleus, and brainstem. The highest MC4R protein levels were found in the ARC and ventromedial hypothalamic nucleus, while they were significantly lower in the parabrachial nucleus and NTS. The lowest MC4R protein levels were found in the PVN; there was no difference in the protein levels between the area postrema and RPa.

Conclusions: These data provide a basic characterization of MC4R-expressing neurons and protein distribution in the mouse brain and may aid further research on its role in energy homeostasis.
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http://dx.doi.org/10.1515/biol-2020-0063DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7874588PMC
August 2020

Genome-Wide Identification and Low Temperature Responsive Pattern of Actin Depolymerizing Factor (ADF) Gene Family in Wheat ( L.).

Front Plant Sci 2021 24;12:618984. Epub 2021 Feb 24.

State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural University, Baoding, China.

The actin depolymerizing factor (ADF) gene family, which is conserved in eukaryotes, is important for plant development, growth, and stress responses. Cold stress restricts wheat growth, development, and distribution. However, genome-wide identification and functional analysis of the ADF family in wheat is limited. Further, because of the promising role of ADF genes in cold response, there is need for an understanding of the function of this family on wheat under cold stress. In this study, 25 ADF genes () were identified in the wheat genome and they are distributed on 15 chromosomes. The TaADF gene structures, duplication events, encoded conversed motifs, and -acting elements were investigated. Expression profiles derived from RNA-seq data and real-time quantitative PCR analysis revealed the tissue- and temporal-specific TaADF expression patterns. In addition, the expression levels of were significantly affected by cold acclimation or freezing conditions. Overexpression of increased the freezing tolerance of transgenic , possibly because of enhanced ROS scavenging and changes to the osmotic regulation in cells. The expression levels of seven cold-responsive genes were up-regulated in the transgenic Arabidopsis plants, regardless of whether the plants were exposed to low temperature. These findings provide fundamental information about the wheat ADF genes and may help to elucidate the regulatory effects of the encoded proteins on plant development and responses to low-temperature stress.
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http://dx.doi.org/10.3389/fpls.2021.618984DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7943747PMC
February 2021

Tailoring Electrolyte Solvation for Li Metal Batteries Cycled at Ultra-Low Temperature.

Nat Energy 2021 25;2021. Epub 2021 Feb 25.

Department of NanoEngineering, University of California, San Diego, La Jolla, CA 92093, USA.

Lithium metal batteries (LMBs) hold the promise to pushing cell level energy densities beyond 300 Wh kg while operating at ultra-low temperatures (< -30°C). Batteries capable of both charging and discharging at these temperature extremes are highly desirable due to their inherent reduction of external warming requirements. Here we demonstrate that the local solvation structure of the electrolyte defines the charge-transfer behavior at ultra-low temperature, which is crucial for achieving high Li metal coulombic efficiency (CE) and avoiding dendritic growth. These insights were applied to Li metal full cells, where a high-loading 3.5 mAh cm sulfurized polyacrylonitrile (SPAN) cathode was paired with a one-fold excess Li metal anode. The cell retained 84 % and 76 % of its room temperature capacity when cycled at -40 and -60 °C, respectively, which presented stable performance over 50 cycles. This work provides design criteria for ultra-low temperature LMB electrolytes, and represents a defining step for the performance of low-temperature batteries.
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http://dx.doi.org/10.1038/s41560-021-00783-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7954221PMC
February 2021

Implementing a comprehensive approach to study the causes of human-bear (Ursus arctos pruinosus) conflicts in the Sanjiangyuan region, China.

Sci Total Environ 2021 Jun 2;772:145012. Epub 2021 Feb 2.

Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China. Electronic address:

Personal injury and property loss caused by wildlife often deteriorates the relationship between humans and animals, prompting retaliatory killings that threaten species survival. Conflicts between humans and Tibetan brown bears (Ursus arctos pruinosus) (Human-Bear Conflicts, HBC) in the Sanjiangyuan region have recently dramatically increased, seriously affecting community enthusiasm for brown bears and the conservation of other species. In order to understand the driving mechanisms of HBC, we proposed six potential drivers leading to increased occurrences of HBC. We conducted field research in Zhiduo County of the Sanjiangyuan region from 2017 to 2019 to test hypotheses through semi-constructed interviews, marmot (Marmota himalayana) density surveys and brown bear diet analysis based on metagenomic sequencing. Analysis of herder perceptions revealed that the driving factors of HBC were related to changes in their settlement practice and living habits, changes in foraging behavior of brown bears and recovery of the brown bear population. Since the establishment of winter homes, brown bears have gradually learned to utilize the food in unattended homes. Although 91.4% (n = 285) of the respondents no longer store food in unattended homes, brown bears were reported to still frequently approach winter homes for food due to improper disposal of dead livestock and household garbage. The frequency and abundance of marmots were found to be high in brown bear diet, indicating that marmots were the bears' primary food. However, marmot density had no significant effect on brown bears utilizing human food (P = 0.329), and HBC appears to not be caused by natural food shortages. Distance to rocky outcrops (P = 0.022) and winter homes (P = 0.040) were the key factors linked to brown bears pursuing human food. The number of brown bears has increased over the past decade, and HBC is likely linked to its population recovery. Our findings will provide scientific basis for formulating effective mitigation measures and protection countermeasures for brown bears.
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http://dx.doi.org/10.1016/j.scitotenv.2021.145012DOI Listing
June 2021

3D Printed Flexible Strain Sensors: From Printing to Devices and Signals.

Adv Mater 2021 Feb 14;33(8):e2004782. Epub 2021 Jan 14.

Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE), Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an, 710072, P. R. China.

The revolutionary and pioneering advancements of flexible electronics provide the boundless potential to become one of the leading trends in the exploitation of wearable devices and electronic skin. Working as substantial intermediates for the collection of external mechanical signals, flexible strain sensors that get intensive attention are regarded as indispensable components in flexible integrated electronic systems. Compared with conventional preparation methods including complicated lithography and transfer printing, 3D printing technology is utilized to manufacture various flexible strain sensors owing to the low processing cost, superior fabrication accuracy, and satisfactory production efficiency. Herein, up-to-date flexible strain sensors fabricated via 3D printing are highlighted, focusing on different printing methods based on photocuring and materials extrusion, including Digital Light Processing (DLP), fused deposition modeling (FDM), and direct ink writing (DIW). Sensing mechanisms of 3D printed strain sensors are also discussed. Furthermore, the existing bottlenecks and future prospects are provided for further progressing research.
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http://dx.doi.org/10.1002/adma.202004782DOI Listing
February 2021

miR-340-5p inhibits sheep adipocyte differentiation by targeting ATF7.

Anim Sci J 2020 Jan;91(1):e13462

College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, China.

Several microRNAs (miRNAs) have been identified to play roles in adipocyte differentiation. However, little is known about their involvement in the differentiation of ovine intramuscular adipocytes. Here, the role of one such miRNA, miR-340-5p, in ovine adipocyte differentiation was investigated. Stromal vascular (SV) cells were isolated from skeletal muscle tissues of 1-month-old lambs and induced to differentiate into mature adipocytes. miRNA mimics and inhibitors were used for miR-340-5p overexpression and knockdown assays. For overexpression and knockdown of activating transcription factor 7 (ATF7), lentivirus infection was performed. Luciferase reporter assay was performed to determine the relationship between miR-340-5p and ATF7. The expression of adipogenesis marker genes, PPARγ, C/EBPα, FABP4, ADIPOQ, and ACC, and formation of lipid droplets were detected after the overexpression and inhibition of miR-340-5p, or upon overexpression or knockdown of ATF7. miR-340-5p inhibited the expression of the marker genes and the formation of lipid droplets. ATF7 positively regulated the expression of the marker genes and the formation of lipids. Thus, ATF7 is the target of miR-340-5p in sheep. Overall, these findings indicate that miR-340-5p acts as an inhibitor of the differentiation of intramuscular adipocytes by targeting ATF7. Our study provides a new theoretical basis for improving sheep meat quality.
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http://dx.doi.org/10.1111/asj.13462DOI Listing
January 2020

Efficient Direct Recycling of Degraded LiMnO Cathodes by One-Step Hydrothermal Relithiation.

ACS Appl Mater Interfaces 2020 Nov 5;12(46):51546-51554. Epub 2020 Nov 5.

Due to the large demand of lithium-ion batteries (LIBs) for energy storage in daily life and the limited lifetime of commercial LIB cells, exploring green and sustainable recycling methods becomes an urgent need to mitigate the environmental and economic issues associated with waste LIBs. In this work, we demonstrate an efficient direct recycling method to regenerate degraded lithium manganese oxide (LMO) cathodes to restore their high capacity, long cycling stability, and high rate performance, on par with pristine LMO materials. This one-step regeneration, achieved by a hydrothermal reaction in dilution Li-containing solution, enables the reconstruction of desired stoichiometry and microphase purity, which is further validated by testing spent LIBs with different states of health. Life-cycle analysis suggested the great environmental and economic benefits enabled by this direct regeneration method compared with today's pyro- and hydrometallurgical processes. This work not only represents a fundamental understanding of the relithiation mechanism of spent cathodes but also provides a potential solution for sustainable and closed-loop recycling and remanufacturing of energy materials.
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http://dx.doi.org/10.1021/acsami.0c15704DOI Listing
November 2020

Multi-Omics Analyses Reveal the Molecular Mechanisms Underlying the Adaptation of Wheat ( L.) to Potassium Deprivation.

Front Plant Sci 2020 6;11:588994. Epub 2020 Oct 6.

State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural University, Baoding, China.

Potassium (K) is essential for regulating plant growth and mediating abiotic stress responses. Elucidating the biological mechanism underlying plant responses to K-deficiency is crucial for breeding new cultivars with improved K uptake and K utilization efficiency. In this study, we evaluated the extent of the genetic variation among 543 wheat accessions differing in K-deficiency tolerance at the seedling and adult plant stages. Two accessions, KN9204 and BN207, were identified as extremely tolerant and sensitive to K-deficiency, respectively. The accessions were exposed to normal and K-deficient conditions, after which their roots underwent ionomic, transcriptomic, and metabolomic analyses. Under K-deficient conditions, KN9204 exhibited stronger root growth and maintained higher K concentrations than BN207. Moreover, 19,440 transcripts and 162 metabolites were differentially abundant in the roots of both accessions according to transcriptomic and metabolomic analyses. An integrated analysis of gene expression and metabolite profiles revealed that substantially more genes, including those related to ion homeostasis, cellular reactive oxygen species homeostasis, and the glutamate metabolic pathway, were up-regulated in KN9204 than in BN207 in response to low-K stress. Accordingly, these candidate genes have unique regulatory roles affecting plant K-starvation tolerance. These findings may be useful for further clarifying the molecular changes underlying wheat root adaptations to K deprivation.
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http://dx.doi.org/10.3389/fpls.2020.588994DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7573229PMC
October 2020

Sequence-Defined Peptoids with -OH and -COOH Groups As Binders to Reduce Cracks of Si Nanoparticles of Lithium-Ion Batteries.

Adv Sci (Weinh) 2020 Sep 5;7(18):2000749. Epub 2020 Aug 5.

Institute for Sustainable Energy/College of Sciences Shanghai University Shanghai 200444 China.

Silicone (Si) is one type of anode materials with intriguingly high theoretical capacity. However, the severe volume change associated with the repeated lithiation and delithiation processes hampers the mechanical/electrical integrity of Si anodes and hence reduces the battery's cycle-life. To address this issue, sequence-defined peptoids are designed and fabricated with two tailored functional groups, "-OH" and "-COOH", as cross-linkable polymeric binders for Si anodes of LIBs. Experimental results show that both the capacity and stability of such peptoids-bound Si anodes can be significantly improved due to the decreased cracks of Si nanoparticles. Particularly, the 15-mer peptoid binder in Si anode can result in a much higher reversible capacity (ca. 3110 mAh g) after 500 cycles at 1.0 A g compared to other reported binders in literature. According to the density functional theory (DFT) calculations, it is the functional groups presented on the side chains of peptoids that facilitate the formation of Si-O binding efficiency and robustness, and then maintain the integrity of the Si anode. The sequence-designed polymers can act as a new platform for understanding the interactions between binders and Si anode materials, and promote the realization of high-performance batteries.
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http://dx.doi.org/10.1002/advs.202000749DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7509666PMC
September 2020

Inhibitory effect of central ghrelin on steroid synthesis affecting reproductive health in female mice.

J Steroid Biochem Mol Biol 2020 11 10;204:105750. Epub 2020 Sep 10.

College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot, 010018, China; Vocational and Technical College, Inner Mongolia Agricultural University, Baotou, 014109, China. Electronic address:

Ghrelin is a 28-amino acid peptide hormone that regulates ovarian steroid hormone synthesis; however, there is limited evidence regarding the regulation of this pathway by ghrelin in mice ovary. Thus, we aimed to investigate whether central ghrelin action plays a role in murine reproductive health by inhibiting steroid synthesis. Further, we sought to examine the mechanism of central ghrelin action in ovarian steroid hormone synthesis. After the administration of intracerebroventricular ghrelin (1 nmol), we found reduced serum concentrations of oestradiol and progesterone and reduced secretion of follicle-stimulating hormone and luteinising hormone. Although ghrelin reduced 3β-hydroxysteroid dehydrogenase mRNA and protein levels in the hypothalamus, it did not affect the expression of steroidogenic acute regulatory protein and cytochrome P450 17A1. In the ovary, central ghrelin regulation indirectly inhibited the mRNA and protein levels of steroidogenic acute regulatory protein, cytochrome P450 17A1, and 3β-hydroxysteroid dehydrogenase. Moreover, no changes were observed in the expression of proliferating cell nuclear antigen and phosphorylation of extracellular signal-regulated kinase. We hypothesised that central ghrelin regulation suppressed serum oestradiol and progesterone levels by indirectly inhibiting the expression of steroidogenic acute regulatory protein, cytochrome P450 17A1, and 3β-hydroxysteroid dehydrogenase in the ovary. In this regulation, the suppressed secretion of the follicle-stimulating hormone and luteinising hormone in the pituitary by ghrelin could be involved. Furthermore, hypothalamic 3β-hydroxysteroid dehydrogenase expression is reduced by ghrelin injection.
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http://dx.doi.org/10.1016/j.jsbmb.2020.105750DOI Listing
November 2020

A disordered rock salt anode for fast-charging lithium-ion batteries.

Nature 2020 09 2;585(7823):63-67. Epub 2020 Sep 2.

Department of Nanoengineering, University of California, San Diego, La Jolla, CA, USA.

Rechargeable lithium-ion batteries with high energy density that can be safely charged and discharged at high rates are desirable for electrified transportation and other applications. However, the sub-optimal intercalation potentials of current anodes result in a trade-off between energy density, power and safety. Here we report that disordered rock salt LiVO can be used as a fast-charging anode that can reversibly cycle two lithium ions at an average voltage of about 0.6 volts versus a Li/Li reference electrode. The increased potential compared to graphite reduces the likelihood of lithium metal plating if proper charging controls are used, alleviating a major safety concern (short-circuiting related to Li dendrite growth). In addition, a lithium-ion battery with a disordered rock salt LiVO anode yields a cell voltage much higher than does a battery using a commercial fast-charging lithium titanate anode or other intercalation anode candidates (LiVO and LiVTiS). Further, disordered rock salt LiVO can perform over 1,000 charge-discharge cycles with negligible capacity decay and exhibits exceptional rate capability, delivering over 40 per cent of its capacity in 20 seconds. We attribute the low voltage and high rate capability of disordered rock salt LiVO to a redistributive lithium intercalation mechanism with low energy barriers revealed via ab initio calculations. This low-potential, high-rate intercalation reaction can be used to identify other metal oxide anodes for fast-charging, long-life lithium-ion batteries.
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http://dx.doi.org/10.1038/s41586-020-2637-6DOI Listing
September 2020

Crystal forms and phase transformation of 1,5-pentanediamine-terephthalate: a bio-based nylon 5T monomer.

Acta Crystallogr B Struct Sci Cryst Eng Mater 2020 Aug 1;76(Pt 4):524-533. Epub 2020 Jul 1.

National Engineering Technique Research Center for Biotechnology, State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, and Jiangsu Synergetic Innovation Center for Advanced Bio-Manufacture, Nanjing Tech University, Nanjing, 210009, People's Republic of China.

Nylon 5T is one of the bio-based nylons, its raw material 1,5-pentanediamine is derived from biomass resources and produced by biological methods. 1,5-pentanediamine-terephthalate (PDA-TPA) is the monomeric salt for nylon 5T polymerization, and its own product quality has a significant impact on the performance of nylon 5T. PDA-TPA was prepared by anti-solvent crystallization in this study. It exists in two solid forms, a monohydrate [form (I)] and an anhydrous phase [form (II)]. The transition temperature of the two phases was around 65°C in the given ethanol-water binary (7:1) mixture. The characterization of monohydrate and anhydrate phases regarding structures and stabilities was carefully carried out using powder X-ray diffraction, single crystal X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, hot-stage microscopy and Fourier transform infrared spectroscopy. The relationship between the molecular interactions of monohydrate and anhydrate phases under different packing architectures and their thermal behaviours was analysed and established. In addition, the relationships between the structures and thermal behaviours for the two solid forms were analysed and established. In addition, the effect of solvent on phase conversion, the relationships between the temperature and water activity, as well as the relative stability of monohydrate and anhydrate phases under different thermodynamic conditions, were investigated by solid-solid transformation and solvent-mediated transformation experiments. It was obvious that the transition temperature of monohydrate and anhydrate phases of PDA-TPA was significantly influenced by water activity, and the larger the value of water activity is, the higher is the transition temperature. These studies give insight into the transformation of nylon 5T monomer salt and contribute to the control of target crystal preparation.
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http://dx.doi.org/10.1107/S2052520620006265DOI Listing
August 2020

Percussion Drilling of Deep Holes Using Picosecond Ultrashort Pulse Laser in Ni-Based Superalloy Coated with Ceramic Thermal Barrier Coatings.

Materials (Basel) 2020 Aug 13;13(16). Epub 2020 Aug 13.

School of Materials Engineering, Shanghai University of Engineering Science, Shanghai 201620, China.

Ni-based superalloy with ceramic thermal barrier coatings (TBCs) is a composite material, which can be used in special environments with high temperature and high pressure such as aeroengine blade. In order to improve the cooling effect of the aeroengine, it is necessary to perform multi-size and large-area holes processing on the surface of blades. As a non-contact processing method with fast processing speed, good processing quality and almost no deformation, laser processing has been one of the important processing methods for film cooling hole processing of aeroengine blades. Percussion drilling is presented using picosecond ultrashort pulse laser in order to explore processing of deep holes in Ni-based superalloy, ceramic TBCs, and ceramic TBCs/substrate multilayer material. The effects of pulses, threshold and wavelength on hole diameter have been discussed, and the experiment on the deep hole ablation with 1064 nm wavelength has been performed. By analyzing the hole size and morphological characteristics of multiple processing parameters, the variation of hole cylindricity is obtained. A high-quality hole, without spatters around the periphery of hole entrance and without recast layer on the side-wall surface, in Ni-based superalloy coated with ceramic TBCs has been drilled. This research has potential applications to blade film cooling holes.
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http://dx.doi.org/10.3390/ma13163570DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7475972PMC
August 2020

Mn-Substituted Li-Rich LiMnMnTiO Materials with High Energy Density.

ACS Appl Mater Interfaces 2020 Sep 25;12(36):40347-40354. Epub 2020 Aug 25.

State Key Laboratory for Physical Chemistry of Solid Surfaces, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.

In this work, Li-rich LiMnMnTiO (LMMTO, 0 ≤ ≤ 0.4) oxides have been studied for the first time. X-ray diffraction (XRD) patterns show a cation-disordered rocksalt structure when ranges from 0 to 0.2. After Mn substitution, LMMTO delivers a high specific capacity of 322 mAh g at room temperature (30 °C, 30 mA g) and even 352 mAh g (45 °C, 30 mA g) with an energy density of 1041 Wh kg. The reason for such a high capacity of LMMTO is ascribed to the increase of both cationic (Mn) and anionic (O) redox after Mn substitution, which is proved by d/d curves, X-ray absorption near edge structure, DFT calculations, and XRD results. In addition, the roles of Mn and Ti in LMMTO are also discussed in detail. A ternary phase diagram is established to comprehend and further optimize the earth-abundant Mn-Mn-Ti system. This work gives an innovative strategy to improve the energy density, broadening the ideas of designing Li-rich materials with better performance.
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http://dx.doi.org/10.1021/acsami.0c11544DOI Listing
September 2020

The stability of P2-layered sodium transition metal oxides in ambient atmospheres.

Nat Commun 2020 Jul 15;11(1):3544. Epub 2020 Jul 15.

State Key Laboratory for Physical Chemistry of Solid Surfaces, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, 361005, Xiamen, People's Republic of China.

Air-stability is one of the most important considerations for the practical application of electrode materials in energy-harvesting/storage devices, ranging from solar cells to rechargeable batteries. The promising P2-layered sodium transition metal oxides (P2-NaTmO) often suffer from structural/chemical transformations when contacted with moist air. However, these elaborate transitions and the evaluation rules towards air-stable P2-NaTmO have not yet been clearly elucidated. Herein, taking P2-NaMnO and P2-NaNiMnO as key examples, we unveil the comprehensive structural/chemical degradation mechanisms of P2-NaTmO in different ambient atmospheres by using various microscopic/spectroscopic characterizations and first-principle calculations. The extent of bulk structural/chemical transformation of P2-NaTmO is determined by the amount of extracted Na, which is mainly compensated by Na/H exchange. By expanding our study to a series of Mn-based oxides, we reveal that the air-stability of P2-NaTmO is highly related to their oxidation features in the first charge process and further propose a practical evaluating rule associated with redox couples for air-stable NaTmO cathodes.
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http://dx.doi.org/10.1038/s41467-020-17290-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7363866PMC
July 2020

Hierarchical Design of MnP Nanoparticles Embedded in N,P-Codoped Porous Carbon Nanosheets Enables Highly Durable Lithium Storage.

ACS Appl Mater Interfaces 2020 Aug 24;12(32):36247-36258. Epub 2020 Jul 24.

Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen, Fujian 361005, China.

Although transition metal phosphide anodes possess high theoretical capacities, their inferior electronic conductivities and drastic volume variations during cycling lead to poor rate capability and rapid capacity fading. To simultaneously overcome these issues, we report a hierarchical heterostructure consisting of isolated MnP nanoparticles embedded into nitrogen- and phosphorus-codoped porous carbon nanosheets (denoted as MnP@NPC) as a viable anode for lithium-ion batteries (LIBs). The resulting MnP@NPC design manifests outstanding electrochemical performances, namely, high reversible capacity (598 mA h g after 300 cycles at 0.1 A g ), exceptional rate capability (347 mA h g at 4 A g), and excellent cycling stability (99% capacity retention at 4 A g after 2000 cycles). The robust structure stability of MnP@NPC electrode during cycling has been revealed by the and transmission electron microscopy (TEM) characterizations, giving rise to long-term cyclability. Using selected area electron diffraction and high-resolution TEM studies, we have unraveled the dominant lithium storage mechanism and confirmed that the superior lithium storage performance of MnP@NPC originated from the reversible conversion reaction. Furthermore, the prelithiated MnP@NPC∥LiFePO full cell exhibits impressive rate capability and cycling stability. This work introduces the potential for engineering high-performance anodes for next-generation high-energy-density LIBs.
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http://dx.doi.org/10.1021/acsami.0c11678DOI Listing
August 2020

Achieving Fast and Durable Lithium Storage through Amorphous FeP Nanoparticles Encapsulated in Ultrathin 3D P-Doped Porous Carbon Nanosheets.

ACS Nano 2020 Aug 23;14(8):9545-9561. Epub 2020 Jul 23.

Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen, Fujian 361005, China.

Conversion-type transition-metal phosphide anode materials with high theoretical capacity usually suffer from low-rate capability and severe capacity decay, which are mainly caused by their inferior electronic conductivities and large volumetric variations together with the poor reversibility of discharge product (LiP), impeding their practical applications. Herein, guided by density functional theory calculations, these obstacles are simultaneously mitigated by confining amorphous FeP nanoparticles into ultrathin 3D interconnected P-doped porous carbon nanosheets (denoted as FeP@CNs) a facile approach, forming an intriguing 3D flake-CNs-like configuration. As an anode for lithium-ion batteries (LIBs), the resulting FeP@CNs electrode not only reaches a high reversible capacity (837 mA h g after 300 cycles at 0.2 A g) and an exceptional rate capability (403 mA h g at 16 A g) but also exhibits extraordinary durability (2500 cycles, 563 mA h g at 4 A g, 98% capacity retention). By combining DFT calculations, transmission electron microscopy, and a suite of microscopic and spectroscopic techniques, we show that the superior performances of FeP@CNs anode originate from its prominent structural and compositional merits, which render fast electron/ion-transport kinetics and abundant active sites (amorphous FeP nanoparticles and structural defects in P-doped CNs) for charge storage, promote the reversibility of conversion reactions, and buffer the volume variations while preventing pulverization/aggregation of FeP during cycling, thus enabling a high rate and highly durable lithium storage. Furthermore, a full cell composed of the prelithiated FeP@CNs anode and commercial LiFePO cathode exhibits impressive rate performance while maintaining superior cycling stability. This work fundamentally and experimentally presents a facile and effective structural engineering strategy for markedly improving the performance of conversion-type anodes for advanced LIBs.
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http://dx.doi.org/10.1021/acsnano.9b08575DOI Listing
August 2020

Alternative strategies of nutrient acquisition and energy conservation map to the biogeography of marine ammonia-oxidizing archaea.

ISME J 2020 10 7;14(10):2595-2609. Epub 2020 Jul 7.

School of Oceanography, University of Washington, Seattle, WA, USA.

Ammonia-oxidizing archaea (AOA) are among the most abundant and ubiquitous microorganisms in the ocean, exerting primary control on nitrification and nitrogen oxides emission. Although united by a common physiology of chemoautotrophic growth on ammonia, a corresponding high genomic and habitat variability suggests tremendous adaptive capacity. Here, we compared 44 diverse AOA genomes, 37 from species cultivated from samples collected across diverse geographic locations and seven assembled from metagenomic sequences from the mesopelagic to hadopelagic zones of the deep ocean. Comparative analysis identified seven major marine AOA genotypic groups having gene content correlated with their distinctive biogeographies. Phosphorus and ammonia availabilities as well as hydrostatic pressure were identified as selective forces driving marine AOA genotypic and gene content variability in different oceanic regions. Notably, AOA methylphosphonate biosynthetic genes span diverse oceanic provinces, reinforcing their importance for methane production in the ocean. Together, our combined comparative physiological, genomic, and metagenomic analyses provide a comprehensive view of the biogeography of globally abundant AOA and their adaptive radiation into a vast range of marine and terrestrial habitats.
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http://dx.doi.org/10.1038/s41396-020-0710-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7490402PMC
October 2020

Effects of amylin on food intake and body weight via sympathetic innervation of the interscapular brown adipose tissue.

Nutr Neurosci 2020 Apr 25:1-13. Epub 2020 Apr 25.

Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot, People's Republic of China.

Amylin acts on the lateral dorsal tegmental nucleus (LDT), resulting in anorexic and weight-loss effects and activates thermogenesis in the interscapular brown adipose tissue (IBAT). In addition, it induces neuronal nitric oxide synthase (nNOS) and choline acetyltransferase (ChAT)-mediated feeding. However, the influence of the intact sympathetic nervous system (SNS) in mediating amylin's effects has not been fully characterised. We investigated whether extracellular signal-regulated kinase (ERK), nNOS, and ChAT activities in the LDT are responsible for amylin's anorexigenic effects and whether this requires an intact SNS. C57BL/6J mice [wild-type (WT), sham, and sympathetic denervation of IBAT] were used. Food consumption, body weight, and distribution of ERK, nNOS, and ChAT positive neurons in the brain were examined following acute and chronic amylin administration. Food intake was significantly decreased in WT and sham animals following acute amylin injection, but not in the denervated mice. Chronic amylin reduced body weight and serum glucose levels after 6 weeks, but increased insulin levels; no changes were observed in the denervated mice. Acute amylin increased the expression of nNOS, ChAT, and uncoupling protein-1 in the IBAT of WT and sham mice, while no changes were observed in the denervated mice and ERK from the above effect. Intact SNS of IBAT influences amylin-induced suppression of food intake and body weight, thus affecting nNOS and ChAT signalling in the LDT and locus coeruleus.
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http://dx.doi.org/10.1080/1028415X.2020.1752998DOI Listing
April 2020

Response of the expression of oxytocin neurons to ghrelin in female mice.

Exp Brain Res 2020 Apr 25;238(4):1085-1095. Epub 2020 Mar 25.

College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, China.

Ghrelin is an orexigenic agonist that acts directly on neurons in the hypothalamus, controlling appetite and energy balance. Although its role in appetite-associated neurons has been described, the relationship between peripheral ghrelin stimulation and oxytocin expression in the paraventricular nucleus is not fully understood. We evaluated the suppressive function of ghrelin in oxytocin-positive paraventricular nucleus neurons in ovariectomized C57BL/6 mice 2 h after ghrelin injection. The results showed that, in intact mice, peripheral ghrelin stimulation activated estrogen receptor alpha-expressing neurons during the estrous cycle and that agouti-related peptide mRNA expression was remarkably increased. Agouti-related peptide neuron axons co-localized with oxytocin neurons in the paraventricular nucleus. Moreover, the response of oxytocin-positive paraventricular nucleus neurons to ghrelin was suppressed in the proestrus period, while ghrelin decreased the serum concentration of estradiol in the proestrus phase. These data suggest that ghrelin may suppress oxytocin-positive neuron expression via the arcuate nucleus agouti-related peptide circuit, with the possible influence of estradiol in the murine estrous cycle. Unraveling the mechanism of ghrelin-induced oxytocin expression in the hypothalamus paraventricular nucleus broadens the horizon for ghrelin-related appetite research.
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http://dx.doi.org/10.1007/s00221-020-05793-zDOI Listing
April 2020

Recognition of V/V/V Multielectron Reactions in NaV(PO): A Potential High Energy Density Cathode for Sodium-Ion Batteries.

Molecules 2020 Feb 24;25(4). Epub 2020 Feb 24.

Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory for Physical Chemistry of Solid Surface, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.

NaV(PO) was reported recently as a novel cathode material with high theoretical energy density for Sodium-ion batteries (SIBs). However, whether V/V/V multielectron reactions can be realized during the charging process is still an open question. In this work, NaV(PO) is synthesized by using a solid-state method. Its atomic composition and crystal structure are verified by X-ray diffraction (XRD) and neutron diffraction (ND) joint refinement. The electrochemical performance of NaV(PO) is evaluated in two different voltage windows, namely 2.5-3.8 and 2.5-4.3 V. V solid-state NMR (ssNMR) results disclose the presence of V in NaV(PO) when charging NaV(PO) to 4.3 V, confirming NaV(PO) is a potential high energy density cathode through realization of V/V/V multielectron reactions.
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http://dx.doi.org/10.3390/molecules25041000DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7070626PMC
February 2020

Enabling Rapid Charging Lithium Metal Batteries via Surface Acoustic Wave-Driven Electrolyte Flow.

Adv Mater 2020 Apr 18;32(14):e1907516. Epub 2020 Feb 18.

Materials Science and Engineering Program and the Department of Mechanical and Aerospace Engineering, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.

Both powerful and unstable, practical lithium metal batteries have remained a difficult challenge for over 50 years. With severe ion depletion gradients in the electrolyte during charging, they rapidly develop porosity, dendrites, and dead Li that cause poor performance and, all too often, spectacular failure. Remarkably, incorporating a small, 100 MHz surface acoustic wave device (SAW) solves this problem. Providing acoustic streaming electrolyte flow during charging, the device enables dense Li plating and avoids porosity and dendrites. SAW-integrated Li cells can operate up to 6 mA cm in a commercial carbonate-based electrolyte; omitting the SAW leads to short circuiting at 2 mA cm . The Li deposition is morphologically dendrite-free and close to theoretical density when cycling with the SAW. With a 245 µm thick Li anode in a full Li||LFP (LiFePO ) cell, introducing the SAW increases the uncycled Li from 145 to 225 µm, decreasing Li consumption from 41% to only 8%. A closed-form model is provided to explain the phenomena and serve as a design tool for integrating this chemistry-agnostic approach into batteries whatever the chemistry within.
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http://dx.doi.org/10.1002/adma.201907516DOI Listing
April 2020

Draining Over Blocking: Nano-Composite Janus Separators for Mitigating Internal Shorting of Lithium Batteries.

Adv Mater 2020 Mar 11;32(12):e1906836. Epub 2020 Feb 11.

Department of Nanoengineering, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.

Catastrophic battery failure due to internal short is extremely difficult to detect and mitigate. In order to enable the next-generation lithium-metal batteries, a "fail safe" mechanism for internal short is highly desirable. Here, a novel separator design and approach is introduced to mitigate the effects of an internal short circuit by limiting the self-discharge current to prevent cell temperature rise. A nano-composite Janus separator-with a fully electronically insulating side contacting the anode and a partially electronically conductive (PEC) coating with tunable conductivity contacting the cathode-is implemented to intercept dendrites, control internal short circuit resistance, and slowly drain cell capacity. Galvanostatic cycling experiments demonstrate Li-metal batteries with the Janus separator perform normally before shorting, which then results in a gradual increase of internal self-discharge over >25 cycles due to PEC-mitigated shorting. This is contrasted by a sudden voltage drop and complete failure seen with a single layer separator. Potentiostatic charging abuse tests of Li-metal pouch cells result in dendrites completely penetrating the single-layer separator causing high short circuit current and large cell temperature increase; conversely, negligible current and temperature rise occurs with the Janus separator where post mortem electron microscopy shows the PEC layer successfully intercepts dendrites.
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http://dx.doi.org/10.1002/adma.201906836DOI Listing
March 2020

Contrasting bacterial and archaeal distributions reflecting different geochemical processes in a sediment core from the Pearl River Estuary.

AMB Express 2020 Jan 22;10(1):16. Epub 2020 Jan 22.

Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen, China.

Microbial community structure and metabolic activities have profound impacts on biogeochemical processes in marine sediments. Functional bacteria such as nitrate- and sulfate-reducing bacteria respond to redox gradients by coupling specific reactions amenable to relevant energy metabolisms. However, similar functional patterns have not been observed for sedimentary archaea (except for anaerobic methanotrophs and methanogens). We coupled taxonomic composition with comprehensive geochemical species to investigate the participation of distinct bacteria and archaea in sedimentary geochemical cycles in a sediment core (300 cm) from Pearl River Estuary (PRE). Geochemical properties (NO, dissolved Mn and Fe, SO, NH; dissolved inorganic carbon (DIC), δC, dissolved organic carbon (DOC), total organic carbon (TOC), δC, and fluorescent dissolved organic matter (FDOM)) exhibited strong depth variability of different trends. Bacterial 16S rRNA- and dsrB gene abundance decreased sharply with depth while archaeal and bathyarchaeotal 16S rRNA gene copies were relatively constant. This resulted in an increase in relative abundance of archaea from surface (11.6%) to bottom (42.8%). Network analysis showed that bacterial groups of Desulfobacterales, Syntrophobacterales and Gammaproteobacteria were significantly (P < 0.0001) associated with SO and dissolved Mn while archaeal groups of Bathyarchaeota, Group C3 and Marine Benthic Group D (MBGD) showed close positive correlations (P < 0.0001) with NH, δC values and humic-like FDOM. Our study suggested that these bacterial groups dominated in redox processes relevant to sulfate or metal oxides, while the archaeal groups are more like to degrade recalcitrant organic compounds in anaerobic sediments.
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http://dx.doi.org/10.1186/s13568-020-0950-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6975606PMC
January 2020

Tuning Oxygen Redox Reaction through the Inductive Effect with Proton Insertion in Li-Rich Oxides.

ACS Appl Mater Interfaces 2020 Feb 29;12(6):7277-7284. Epub 2020 Jan 29.

State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemistry, College of Chemistry and Chemical Engineering, and College of Energy , Xiamen University , Xiamen 361005 , China.

As a parent compound of Li-rich electrodes, LiMnO exhibits high capacity during the initial charge; however, it suffers notoriously low Coulombic efficiency due to oxygen and surface activities. Here, we successfully optimize the oxygen activities toward reversible oxygen redox reactions by intentionally introducing protons into lithium octahedral vacancies in the LiMnO system with its original structural integrity maintained. Combining structural probes, theoretical calculations, and resonant inelastic X-ray scattering results, a moderate coupling between the introduced protons and lattice oxygen at the oxidized state is revealed, which stabilizes the oxygen activities during charging. Such a coupling leads to an unprecedented initial Coulombic efficiency (99.2%) with a greatly improved discharge capacity of 302 mAh g in the protonated LiMnO electrodes. These findings directly demonstrate an effective concept for controlling oxygen activities in Li-rich systems, which is critical for developing high-energy cathodes in batteries.
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http://dx.doi.org/10.1021/acsami.9b21738DOI Listing
February 2020

Identifying the risk regions of house break-ins caused by Tibetan brown bears () in the Sanjiangyuan region, China.

Ecol Evol 2019 Dec 8;9(24):13979-13990. Epub 2019 Dec 8.

Research Institute of Forest Ecology, Environment and Protection Chinese Academy of Forestry Beijing China.

Damage to homesteads by brown bears () has become commonplace in Asia, Europe, and the Americas. Science-based solutions for preventing damages can contribute to the establishment of mechanisms that promote human-bear coexistence. We examined the spatial distribution patterns of house break-ins by Tibetan brown bears () in Zhiduo County of the Sanjiangyuan region in China. Occurrence points of bear damage were collected from field surveys completed from 2017 to 2019. The maximum entropy (MaxEnt) model was then used to assess house break-in risk. Circuit theory modeling was used to simulate risk diffusion paths based on the risk map generated from our MaxEnt model. The results showed that (a) the total risk area of house break-ins caused by brown bears was 11,577.91 km, accounting for 29.85% of Zhiduo County, with most of the risk areas were distributed in Sanjiangyuan National Park, accounting for 58.31% of the total risk area; (b) regions of alpine meadow located in Sanjiangyuan National Park with a high human population density were associated with higher risk; (c) risk diffusion paths extended southeast to northwest, connecting the inside of Sanjiangyuan National Park to its outside border; and (d) eastern Suojia, southern Zhahe, eastern Duocai, and southern Jiajiboluo had more risk diffusion paths than other areas examined, indicating higher risk for brown bear break-ins in these areas. Risk diffusion paths will need strong conservation management to facilitate migration and gene flow of brown bears and to alleviate bear damage, and implementation of compensation schemes may be necessary in risk areas to offset financial burdens. Our analytical methods can be applied to conflict reduction efforts and wildlife conservation planning across the Qinghai-Tibet Plateau.
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http://dx.doi.org/10.1002/ece3.5835DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6953560PMC
December 2019

Metastability and Reversibility of Anionic Redox-Based Cathode for High-Energy Rechargeable Batteries.

Cell Rep Phys Sci 2020 ;1(3)

Department of NanoEngineering, University of California, San Diego, La Jolla, CA 92093, USA.

Great focus has recently been placed on anionic redox, to which high capacities of Li-rich layered oxides are attributed. With almost doubled capacity compared with state-of-the-art cathode materials, Li-rich layered oxides still fall short in other performance metrics. Among these, voltage decay upon cycling remains the most hindering obstacle, in which defect electrochemistry plays a critical role. Here, we reveal that the metastable state of cycled Li-rich layered oxide, which stems from structural defects in different dimensions, is responsible for the voltage decay. More importantly, through mild thermal energy, the metastable state can be driven to a stable state, bringing about structural and voltage recovery. However, for the classic layered oxide without reversible anionic redox, thermal energy can only introduce cation disordering, leading to performance deterioration. These insights elucidate that understanding the structure metastability and reversibility is essential for implementing design strategies to improve cycling stability for high-capacity layered oxides.
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http://dx.doi.org/10.1016/j.xcrp.2020.100028DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7919000PMC
January 2020

Identifying climate refugia and its potential impact on Tibetan brown bear () in Sanjiangyuan National Park, China.

Ecol Evol 2019 Dec 14;9(23):13278-13293. Epub 2019 Nov 14.

Research Institute of Forest Ecology, Environment and Protection Chinese Academy of Forestry Beijing China.

Climate change has direct impacts on wildlife and future biodiversity protection efforts. Vulnerability assessment and habitat connectivity analyses are necessary for drafting effective conservation strategies for threatened species such as the Tibetan brown bear (). We used the maximum entropy (MaxEnt) model to assess the current (1950-2000) and future (2041-2060) habitat suitability by combining bioclimatic and environmental variables, and identified potential climate refugia for Tibetan brown bears in Sanjiangyuan National Park, China. Next, we selected Circuit model to simulate potential migration paths based on current and future climatically suitable habitat. Results indicate a total area of potential suitable habitat under the current climate scenario of approximately 31,649.46 km, of which 28,778.29 km would be unsuitable by the 2050s. Potentially suitable habitat under the future climate scenario was projected to cover an area of 23,738.6 km. Climate refugia occupied 2,871.17 km, primarily in the midwestern and northeastern regions of Yangtze River Zone, as well as the northern region of Yellow River Zone. The altitude of climate refugia ranged from 4,307 to 5,524 m, with 52.93% lying at altitudes between 4,300 and 4,600 m. Refugia were mainly distributed on bare rock, alpine steppe, and alpine meadow. Corridors linking areas of potentially suitable brown bear habitat and a substantial portion of paths with low-resistance value were distributed in climate refugia. We recommend various actions to ameliorate the impact of climate change on brown bears, such as protecting climatically suitable habitat, establishing habitat corridors, restructuring conservation areas, and strengthening monitoring efforts.
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http://dx.doi.org/10.1002/ece3.5780DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6912912PMC
December 2019

Percussion Drilling Hole in Cu, Al, Ti, and Ni Alloys Using Ultra-Short Pulsed Laser Ablation.

Materials (Basel) 2019 Dec 19;13(1). Epub 2019 Dec 19.

State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710049, China.

Comparative study on micro-deep hole drilling by picosecond ultra-short pulse laser in four metals, including copper, aluminum alloy, titanium alloy, and nickel alloy, was presented. Destructive testing was performed to measure the depth, shape, and side-wall morphology of micro-deep holes in this study. Diameters and depths of micro-deep holes in four metals ablated using the same processing parameters were compared. The multiple thresholds of metals had been calculated. Relationships between hole dimensions and multiple thresholds (the average ablation threshold, the ablation threshold and the thermal threshold) and physical properties (for example, the heat capacity, the melting temperature, the optical penetration depth and the absorbance, etc.) of the four metals are examined. Furthermore, the surface and side-wall morphologies of the micro-deep holes in four metals were demonstrated. The influence mechanisms, especially the side-wall morphology, were discussed, such as the thresholds, conical emission, self-cleaning effect, physical properties of metals, the energy transmission, the plasma effect, thermochemical reaction, and so on.
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http://dx.doi.org/10.3390/ma13010031DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6981866PMC
December 2019

Population dynamics of methanogens and methanotrophs along the salinity gradient in Pearl River Estuary: implications for methane metabolism.

Appl Microbiol Biotechnol 2020 Feb 19;104(3):1331-1346. Epub 2019 Dec 19.

Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen, People's Republic of China.

Methane, a major greenhouse gas, plays an important role in global carbon cycling and climate change. Methanogenesis is identified as an important process for methane formation in estuarine sediments. However, the metabolism of methane in the water columns of estuaries is not well understood. The goal of this research was to examine the dynamics in abundance and community composition of methanogens and methanotrophs, and to examine whether and how they take part in methane metabolism in the water columns from the lower Pearl River (freshwater) to the coastal South China Sea (seawater). Quantitative PCR (qPCR) and high-throughput sequencing results showed that the abundance of methanogens decreased with increasing salinity, suggesting that growth of these methanogens in the Pearl River Estuary may be influenced by high salinity. Also, the methane concentration in surface waters was lower than that in near-bottom waters at most sites, suggesting sediment methanogens are a likely source of methane. In the estuarine mixing zone, significantly high methane concentrations existed with the presence of salt-tolerant methanogens (e.g., Methanomicrobiaceae, Methanocella, Methanosaeta and Methanobacterium) and methanotrophs (e.g., Methylocystis and Methylococcaceae), which were found in brackish habitats. Furthermore, a number of methanotrophic OTUs (from pmoA gene sequence data) had specific positive correlations with methanogenic OTUs (from mcrA gene sequence data), and some of these methanogenic OTUs were correlated with concentrations of particulate organic carbon (POC). The results indicate that methanotrophs and methanogens may be intimately linked in methane metabolism attached with particles in estuarine waters.
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http://dx.doi.org/10.1007/s00253-019-10221-6DOI Listing
February 2020