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1.
Science ; 384(6700): 1100-1104, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38843317

ABSTRACT

One-dimensional transition metal dichalcogenides exhibiting an enhanced bulk photovoltaic effect have the potential to exceed the Shockley-Queisser limit efficiency in solar energy harvest within p-n junction architectures. However, the collective output of these prototype devices remains a challenge. We report on the synthesis of single-crystalline WS2 ribbon arrays with defined chirality and coherent polarity through an atomic manufacturing strategy. The chirality of WS2 ribbon was defined by substrate couplings into tunable armchair, zigzag, and chiral species, and the polarity direction was determined by the ribbon-precursor interfacial energy along a coherent direction. A single armchair ribbon showed strong bulk photovoltaic effect and the further integration of ~1000 aligned ribbons with coherent polarity enabled upscaling of the photocurrent.

2.
Nature ; 629(8010): 74-79, 2024 May.
Article in English | MEDLINE | ID: mdl-38693415

ABSTRACT

Within the family of two-dimensional dielectrics, rhombohedral boron nitride (rBN) is considerably promising owing to having not only the superior properties of hexagonal boron nitride1-4-including low permittivity and dissipation, strong electrical insulation, good chemical stability, high thermal conductivity and atomic flatness without dangling bonds-but also useful optical nonlinearity and interfacial ferroelectricity originating from the broken in-plane and out-of-plane centrosymmetry5-23. However, the preparation of large-sized single-crystal rBN layers remains a challenge24-26, owing to the requisite unprecedented growth controls to coordinate the lattice orientation of each layer and the sliding vector of every interface. Here we report a facile methodology using bevel-edge epitaxy to prepare centimetre-sized single-crystal rBN layers with exact interlayer ABC stacking on a vicinal nickel surface. We realized successful accurate fabrication over a single-crystal nickel substrate with bunched step edges of the terrace facet (100) at the bevel facet (110), which simultaneously guided the consistent boron-nitrogen bond orientation in each BN layer and the rhombohedral stacking of BN layers via nucleation near each bevel facet. The pure rhombohedral phase of the as-grown BN layers was verified, and consequently showed robust, homogeneous and switchable ferroelectricity with a high Curie temperature. Our work provides an effective route for accurate stacking-controlled growth of single-crystal two-dimensional layers and presents a foundation for applicable multifunctional devices based on stacked two-dimensional materials.

3.
Appl Microbiol Biotechnol ; 108(1): 292, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38592514

ABSTRACT

Pulchinenoside B4, a natural saponin monomer from the Pulsatilla plant, plays an important role as an immunomodulator in the treatment of acute inflammation. Oral ulcer (OU) is a common ulcerative injury disease that occurs in the oral mucosa, including mucosal ulceration and abnormalities of lips and tongue. A close correlation exists between gut microbiota and circulating metabolites in patients with OU. However, the correlation between gut microbiota and serum metabolomics is not clear. Therefore, this study aimed to explore the changes in gut microbiota and metabolites in OU. The 16S ribosomal RNA (16S rRNA) gene sequencing was used to detect the changes in the composition of gut microbiota in OU rat model. Moreover, the endogenous small metabolites were explored by collecting the non-targeted serum metabolomics data. A total of 34 OU-related biomarkers were identified, mainly related to fatty acid metabolism and inflammatory pathways. The administration of B4 effectively reduced the occurrence of OU and restored the levels of multiple endogenous biomarkers and key gut microbial species to the normal level. This study demonstrated that the gut microbiota and metabolites were altered in the OU rat model, which were significantly restored to the normal level by B4, thereby showing good application prospects in the treatment of OU. KEY POINTS: • The first investigating the correlation between OU and gut microbiota. • A close correlation between metabolites and gut microbiota in OU disease was successfully identified. • Pulchinenoside B4 ameliorates oral ulcers in rats by modulating gut microbiota and metabolites.


Subject(s)
Gastrointestinal Microbiome , Oral Ulcer , Humans , Animals , Rats , RNA, Ribosomal, 16S/genetics , Mouth Mucosa , Biomarkers
4.
Angew Chem Int Ed Engl ; : e202320014, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38598078

ABSTRACT

Amino acids are the building blocks of proteins and are widely used as important ingredients for other nitrogen-containing molecules. Here, we report the sustainable production of amino acids from biomass-derived hydroxy acids with high activity under visible-light irradiation and mild conditions, using atomic ruthenium-promoted cadmium sulfide (Ru1/CdS). On a metal basis, the optimized Ru1/CdS exhibits a maximal alanine formation rate of 26.0 molAla ⋅ gRu -1 ⋅ h-1, which is 1.7 times and more than two orders of magnitude higher than that of its nanoparticle counterpart and the conventional thermocatalytic process, respectively. Integrated spectroscopic analysis and density functional theory calculations attribute the high performance of Ru1/CdS to the facilitated charge separation and O-H bond dissociation of the α-hydroxy group, here of lactic acid. The operando nuclear magnetic resonance further infers a unique "double activation" mechanism of both the CH-OH and CH3-CH-OH structures in lactic acid, which significantly accelerates its photocatalytic amination toward alanine.

5.
Aquat Toxicol ; 270: 106904, 2024 May.
Article in English | MEDLINE | ID: mdl-38513426

ABSTRACT

Due to their potential release into the environment, the ecotoxicity of Ti3C2Tx (MXene) nanomaterials is a growing concern. Unfortunately, little is known about the toxic effects and mechanisms through which Ti3C2Tx induces toxicity in aquatic organisms. The aim of this study is thus to investigate the toxic effects and mechanisms of Daphnia magna upon exposure to Ti3C2Tx with different sheet sizes (100 nm [Ti3C2Tx-100] and 500 nm [Ti3C2Tx-500]) by employing conventional toxicology and metabolomics analysis. The results showed that exposure to both Ti3C2Tx-100 and Ti3C2Tx-500 at 10 µg/mL resulted in a significant accumulation of Ti3C2Tx in D. magna, but no effects on the mortality or growth of D. magna were observed. However, the metabolomics results revealed that Ti3C2Tx-100 and Ti3C2Tx-500 induced significant changes in up to 265 and 191 differential metabolites in D. magna, respectively, of which 116 metabolites were common for both. Ti3C2Tx-100-induced metabolites were mainly enriched in phospholipid, pyrimidine, tryptophan, and arginine metabolism, whereas Ti3C2Tx-500-induced metabolites were mainly enriched in the glycerol-ester, tryptophan, and glyoxylate metabolism and the pentose phosphate pathway. These results indicated that the toxicity of Ti3C2Tx to D. magna has a size-dependent effect at the metabolic level, and both sheet sizes of Ti3C2Tx can lead to metabolic disturbances in D. magna by interfering with lipid and amino acid metabolism pathways.


Subject(s)
Daphnia magna , Nitrites , Transition Elements , Water Pollutants, Chemical , Animals , Daphnia , Titanium/pharmacology , Tryptophan/metabolism , Tryptophan/pharmacology , Water Pollutants, Chemical/toxicity
6.
Phys Rev Lett ; 132(5): 056601, 2024 Feb 02.
Article in English | MEDLINE | ID: mdl-38364175

ABSTRACT

In this Letter, we theoretically explore the physical properties of a new type of three-dimensional graphite moiré superlattice, the bulk alternating twisted graphite (ATG) system with homogeneous twist angle, which is grown by in situ chemical vapor decomposition method. Compared to twisted bilayer graphene (TBG), the bulk ATG system is bestowed with an additional wave vector degree of freedom due to the extra dimensionality. As a result, when the twist angle of bulk ATG is smaller than twice of the magic angle of TBG, there always exist "magic momenta" which host topological flat bands with vanishing in-plane Fermi velocities. Most saliently, when the twist angle is relatively large, a dispersionless three-dimensional zeroth Landau level would emerge in the bulk ATG, which may give rise to robust three-dimensional quantum Hall effects and unusual quantum-Hall physics over a large range of twist angles.

7.
Small Methods ; : e2301319, 2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38178653

ABSTRACT

The nitrogen doping (N-doping) treatment for niobium superconducting radio-frequency (SRF) cavities is one of the key enabling technologies that support the development of more efficient future large accelerators. However, the N-doping results have diverged due to a complex chemical profile under the nitrogen-doped surface. Particularly, under industrial-scale production conditions, it is difficult to understand the underlying mechanism thus hindering performance improvement. Herein, a combination of spatially resolved and surface-sensitive approaches is employed to establish the detailed near-surface phase composition of thermally processed niobium. The results show that intermediate phase segregations, particularly the nanometric carbon-rich phase, can impede the nitridation process and limit the interactions between nitrogen and the niobium sub-surface. In comparison, the removal of the carbon-rich layer at the Nb surface leads to enhanced nitrogen binding at the Nb surface. Combining the RF test results, it is shown that the complex uniformity and grain boundary penetrations of impurity elements have a direct correlation with the mid-field quench behavior in the N-doped Nb cavities. Therefore, proper control of the nanometric intermediate phase formation in discrete thermal steps is critical in improving the ultimate performance and production yield of the Nb cavities.

8.
Small Methods ; : e2301247, 2024 Jan 06.
Article in English | MEDLINE | ID: mdl-38183406

ABSTRACT

Additive microfabrication processes based on localized electroplating enable the one-step deposition of micro-scale metal structures with outstanding performance, e.g., high electrical conductivity and mechanical strength. They are therefore evaluated as an exciting and enabling addition to the existing repertoire of microfabrication technologies. Yet, electrochemical processes are generally restricted to conductive or semiconductive substrates, precluding their application in the manufacturing of functional electric devices where direct deposition onto insulators is often required. Here, the direct, localized electrodeposition of copper on a variety of insulating substrates, namely Al2 O3 , glass and flexible polyethylene, is demonstrated, enabled by electron-beam-induced reduction in a highly confined liquid electrolyte reservoir. The nanometer-size of the electrolyte reservoir, fed by electrohydrodynamic ejection, enables a minimal feature size on the order of 200 nm. The fact that the transient reservoir is established and stabilized by electrohydrodynamic ejection rather than specialized liquid cells can offer greater flexibility toward deposition on arbitrary substrate geometries and materials. Installed in a low-vacuum scanning electron microscope, the setup further allows for operando, nanoscale observation and analysis of the manufacturing process.

9.
Nat Mater ; 23(3): 331-338, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37537355

ABSTRACT

The properties of two-dimensional (2D) van der Waals materials can be tuned through nanostructuring or controlled layer stacking, where interlayer hybridization induces exotic electronic states and transport phenomena. Here we describe a viable approach and underlying mechanism for the assisted self-assembly of twisted layer graphene. The process, which can be implemented in standard chemical vapour deposition growth, is best described by analogy to origami and kirigami with paper. It involves the controlled induction of wrinkle formation in single-layer graphene with subsequent wrinkle folding, tearing and re-growth. Inherent to the process is the formation of intertwined graphene spirals and conversion of the chiral angle of 1D wrinkles into a 2D twist angle of a 3D superlattice. The approach can be extended to other foldable 2D materials and facilitates the production of miniaturized electronic components, including capacitors, resistors, inductors and superconductors.

10.
Microbiome ; 11(1): 276, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-38102689

ABSTRACT

BACKGROUND: Leakages of cold, methane-rich fluids from subsurface reservoirs to the sea floor are termed cold seeps. Recent exploration of the deep sea has shed new light on the microbial communities in cold seeps. However, conventional metagenomic methods largely rely on reference databases and neglect the phylogeny of functional genes. RESULTS: In this study, we developed the REMIRGE program to retrieve the full-length functional genes from shotgun metagenomic reads and fully explored the phylogenetic diversity in cold seep sediments. The abundance and diversity of functional genes involved in the methane, sulfur, and nitrogen cycles differed in the non-seep site and five cold seep sites. In one Haima cold seep site, the divergence of functional groups was observed at the centimeter scale of sediment depths, with the surface layer potentially acting as a reservoir of microbial species and functions. Additionally, positive correlations were found between specific gene sequence clusters of relevant genes, indicating coupling occurred within specific functional groups. CONCLUSION: REMIRGE revealed divergent phylogenetic diversity of functional groups and functional pathway preferences in a deep-sea cold seep at finer scales, which could not be detected by conventional methods. Our work highlights that phylogenetic information is conducive to more comprehensive functional profiles, and REMIRGE has the potential to uncover more new insights from shotgun metagenomic data. Video Abstract.


Subject(s)
Geologic Sediments , Microbiota , Oceans and Seas , Methane/metabolism , Phylogeny , RNA, Ribosomal, 16S/genetics , Metagenomics , Cold Temperature
11.
Nat Commun ; 14(1): 7447, 2023 Nov 17.
Article in English | MEDLINE | ID: mdl-37978192

ABSTRACT

The atomic-thick anticorrosion coating for copper (Cu) electrodes is essential for the miniaturisation in the semiconductor industry. Graphene has long been expected to be the ultimate anticorrosion material, however, its real anticorrosion performance is still under great controversy. Specifically, strong electronic couplings can limit the interfacial diffusion of corrosive molecules, whereas they can also promote the surficial galvanic corrosion. Here, we report the enhanced anticorrosion for Cu simply via a bilayer graphene coating, which provides protection for more than 5 years at room temperature and 1000 h at 200 °C. Such excellent anticorrosion is attributed to a nontrivial Janus-doping effect in bilayer graphene, where the heavily doped bottom layer forms a strong interaction with Cu to limit the interfacial diffusion, while the nearly charge neutral top layer behaves inertly to alleviate the galvanic corrosion. Our study will likely expand the application scenarios of Cu under various extreme operating conditions.

12.
Adv Mater ; 35(36): e2302568, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37285053

ABSTRACT

Fe3 GeTe2 have proven to be of greatly intrigue. However, the underlying mechanism behind the varying Curie temperature (Tc ) values remains a puzzle. This study explores the atomic structure of Fe3 GeTe2 crystals exhibiting Tc values of 160, 210, and 230 K. The elemental mapping reveals a Fe-intercalation on the interstitial sites within the van der Waals gap of the high-Tc (210 and 230 K) samples, which are observed to have an exchange bias effect by electrical transport measurements, while Fe intercalation or the bias effect is absent in the low-Tc (160 K) samples. First-principles calculations further suggest that the Fe-intercalation layer may be responsible for the local antiferromagnetic coupling that gives rise to the exchange bias effect, and that the interlayer exchange paths greatly contribute to the enhancement of Tc . This discovery of the Fe-intercalation layer elucidates the mechanism behind the hidden antiferromagnetic ordering that underlies the enhancement of Tc in Fe3 GeTe2 .

13.
Nano Lett ; 23(12): 5770-5778, 2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37314049

ABSTRACT

Understanding the atomistic mechanisms of non-equilibrium processes during solid-state synthesis, such as nucleation and grain structure formation of a layered oxide phase, is a critical challenge for developing promising cathode materials such as Ni-rich layered oxide for Li-ion batteries. In this study, we found that the aluminum oxide coating layer transforms into lithium aluminate as an intermediate, which has favorable low interfacial energies with the layered oxide to promote the nucleation of the latter. The fast and uniform nucleation and formation of the layered oxide phase at relatively low temperatures were evidenced using solid-state nuclear magnetic resonance and in situ synchrotron X-ray diffraction. The resulting Ni-rich layered oxide cathode has fine primary particles, as visualized by three-dimensional tomography constructed using a focused-ion beam and scanning electron microscopy. The densely packed fine primary particles enable the excellent mechanical strength of the secondary particles, as demonstrated by in situ compression tests. This strategy provides a new approach for developing next-generation, high-strength battery materials.

14.
Angew Chem Int Ed Engl ; 62(23): e202219241, 2023 Jun 05.
Article in English | MEDLINE | ID: mdl-37017231

ABSTRACT

Metal-organic framework catalysts bring new opportunities for CO2 electrocatalysis. Herein, we first conduct density-functional theory calculations and predict that Co-based porphyrin porous organic layers (Co-PPOLs) exhibit good activity for CO2 conversion because of the low *CO adsorption energy at Co-N4 sites, which facilitates *CO desorption and CO formation. Then, we prepare two-dimensional Co-PPOLs with exclusive Co-N4 sites through a facile surfactant-assisted bottom-up method. The ultrathin feature ensures the exposure of catalytic centers. Together with large specific area, high electrical conductivity and CO2 adsorption capability, Co-PPOLs achieve a peak faradaic efficiency for CO production (FECO =94.2 %) at a moderate potential in CO2 electroreduction, accompanied with good stability. Moreover, Co-PPOLs reach an industrial-level current above 200 mA in a membrane electrode assembly reactor, and maintain near-unity CO selectivity (FECO >90 %) over 20 h in CO2 electrolysis.

15.
Article in English | MEDLINE | ID: mdl-37027265

ABSTRACT

Magnetic leakage detection technology plays an important role in the long-oil pipeline. Automatic segmentation of defecting images is crucial for the detection of magnetic flux leakage (MFL) works. At present, accurate segmentation for small defects has always been a difficult problem. In contrast to the state-of-the-art MFL detection methodologies based on convolution neural network (CNN), an optimization method is devised in our study by integrating mask region-based CNN (Mask R-CNN) and information entropy constraint (IEC). To be precise, the principal component analysis (PCA) is utilized to improve the feature learning and network segmentation ability of the convolution kernel. The similarity constraint rule of information entropy is proposed to be inserted into the convolution layer in the Mask R-CNN network. The Mask R-CNN optimizes the convolutional kernel with similar weights or higher similarity, meanwhile, the PCA network reduces the dimension of the feature image to reconstruct the original feature vector. As such, the feature extraction of MFL defects is optimized in the convolution check. The research results can be applied in the field of MFL detection.

16.
Curr Med Sci ; 43(2): 255-260, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36943542

ABSTRACT

OBJECTIVE: This study was to examine the relationship between socioeconomic status and the incidence and mortality of non-Hodgkin lymphoma (NHL). METHODS: We compared the age-standardized incidence rate (ASIR), age-standardized mortality rate (ASMR), and the ASMR to ASIR ratio (MIR) at national and regional levels and studied the correlation between the MIR and the human development index (HDI) in 2012 and 2018. RESULTS: The highest ASIR was in North America in 2012 and in Australia in 2018, and the lowest ASIR was in Central and South Asia in both 2012 and 2018. The highest ASMR was in North Africa in both 2012 and 2018, and the lowest ASMR was in Eastern Asia and South-Central Asia in 2012 and in South-Central Asia in 2018. The lowest MIR was in Australia in both 2012 and 2018, and the highest MIR was in Western Africa in both 2012 and 2018. HDI was strongly negatively correlated with MIR (r: -0.8810, P<0.0001, 2012; r: -0.8895, P<0.0001, 2018). Compared to the 2012 data, the MIR in the intermediate HDI countries significantly deceased and the HDI in low and high HDI countries significantly increased in 2018. CONCLUSION: The MIR is negatively correlated with HDI. Increasing the HDI in low and intermediate HDI countries may reduce the MIR and increase the survival of patients with NHL.


Subject(s)
Lymphoma, Non-Hodgkin , Humans , Incidence , Asia, Southern , Lymphoma, Non-Hodgkin/epidemiology
17.
Se Pu ; 41(3): 207-223, 2023 Mar.
Article in Chinese | MEDLINE | ID: mdl-36861204

ABSTRACT

Ciwujia injection is commonly used to treat cerebrovascular and central nervous system diseases in clinical practice. It can significantly improve blood lipid levels and endothelial cell function in patients with acute cerebral infarction and promote the proliferation of neural stem cells in cerebral ischemic brain tissues. The injection has also been reported to have good curative effects on cerebrovascular diseases, such as hypertension and cerebral infarction. At present, the material basis of Ciwujia injection remains incompletely understood, and only two studies have reported dozens of components, which were determined using high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF MS). Unfortunately, the lack of research on this injection restricts the in-depth study of its therapeutic mechanism.In the present study, a qualitative method based on ultra-high performance liquid chromatography-quadrupole-electrostatic field orbitrap high-resolution mass spectrometry (UHPLC-Q/Orbitrap HRMS) was developed to analyze the chemical components of Ciwujia injection. Separation was performed on a BEH Shield RP18 column (100 mm×2.1 mm, 1.7 µm) using 0.1% formic acid aqueous solution (A) and acetonitrile (B) as the mobile phases, and gradient elution was performed as follows: 0-2 min, 0%B; 2-4 min, 0%B-5%B; 4-15 min, 5%B-20%B; 15-15.1 min, 20%B-90%B; 15.1-17 min, 90%B. The flow rate and column temperature were set to 0.4 mL/min and 30 ℃ respectively. MS1 and MS2 data were acquired in both positive- and negative-ion modes using a mass spectrometer equipped with an HESI source. For data post-processing, a self-built library including component names, molecular formulas, and chemical structures was established by collecting information on the isolated chemical compounds of Acanthopanax senticosus. The chemical components of the injection were identified by comparison with standard compounds or MS2 data in commercial databases or literature based on precise relative molecular mass and fragment ion information. The fragmentation patterns were also considered. For example, the MS2 data of 3-caffeoylquinic acid (chlorogenic acid), 4-caffeoylquinic acid (cryptochlorogenic acid), and 5-caffeoylquinic acid (neochlorogenic acid) were first analyzed. The results indicated that these compounds possessed similar fragmentation behaviors, yielding product ions at m/z 173 and m/z 179 simultaneously. However, the abundance of the product ion at m/z 173 was much higher in 4-caffeoylquinic acid than in 5-caffeoylquinic acid or 3-caffeoylquinic acid, and the fragment signal at m/z 179 was much stronger for 5-caffeoylquinic acid than for 3-caffeoylquinic acid. Four caffeoylquinic acids were identified using a combination of abundance information and retention times. MS2 data in commercial database and literature were also used to identify unknown constituents. For example, compound 88 was successfully identified as possessing a relative molecular mass and neutral losses similar to those of sinapaldehyde using the database, and compound 80 was identified as salvadoraside because its molecular and fragmentation behaviors were consistent with those reported in the literature. A total of 102 constituents, including 62 phenylpropanoids, 23 organic acids, 7 nucleosides, 1 iridoid, and 9 other compounds, were identified. The phenylpropanoids can be further classified as phenylpropionic acids, phenylpropanols, benzenepropanals, coumarins, and lignans. Among the detected compounds, 16 compounds were confirmed using reference compounds and 65 compounds were identified in Ciwujia injection for the first time. This study is the first to report the feasibility of using the UHPLC-Q/Orbitrap HRMS method to quickly and comprehensively analyze the chemical components of Ciwujia injection. The 27 newly discovered phenylpropanoids provide further material basis for the clinical treatment of neurological diseases and new research targets for the in-depth elucidation of the pharmacodynamic mechanism of Ciwujia injection and its related preparations.


Subject(s)
Eleutherococcus , Humans , Chromatography, High Pressure Liquid , Chlorogenic Acid , Static Electricity
18.
Nat Mater ; 22(1): 144-145, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36513891
19.
mSystems ; 7(5): e0082122, 2022 10 26.
Article in English | MEDLINE | ID: mdl-36200770

ABSTRACT

The linkages between phytoplankton and zooplankton are crucial for the stability of complex food webs and the flow of energy within the marine ecosystem. Despite body size exhibiting multiple effects on the planktonic community assembly and the dispersal scale, its role in determining the stability of phyto-zooplanktonic co-occurrence patterns remains unclear. Here, we focused on more than 13,000 kilometers of the Chinese coast to study the diatom-dominated plankton ecosystem and to report the significant negative effects of zooplanktonic body sizes on the topological properties of phyto-zooplanktonic networks (PZNs) by using more than 500 species from 251 samples taken along the coastline. PZNs tended to be more complex and stable when phytoplankton associated with smaller zooplankton. Particularly, the subnetworks of dominant phytoplankton displayed differences with different zooplanktonic body sizes. The zooplankton with larger and smaller body sizes tended to interact with dinoflagellates and diatoms, respectively. Additionally, abiotic factors (i.e., water temperature, pH, salinity, and metal concentrations) displayed significant effects on PZNs via the shifting of zooplanktonic composition, and the zooplanktonic body sizes altered the network modules' associations with different environmental factors. Our study elucidated the general relationship between zooplanktonic body sizes and the stability of PZNs, which provides new insights into marine food webs. IMPORTANCE Body size is a key life trait of aquatic plankton that affects organisms' metabolic rates and ecological functions; however, its specific effects on interactions between phytoplankton and zooplankton are poorly understood. We collected planktonic species and their body size data along more than 13,000 kilometers of coastline to explore the role of zooplanktonic body size in maintaining the stability of phyto-zooplanktonic networks (PZNs). We found that zooplankton play a more important role in maintaining PZN stability than do phytoplankton as well as that the PZN would be more complex and stable with smaller zooplankton. Furthermore, this work revealed that body size significantly determined the relationships between environmental factors and network structure. Overall, these findings lay a general relationship between zooplanktonic body sizes and the stability of PZNs, which helps us further explore the micro food web of coastal ecosystems.


Subject(s)
Diatoms , Ecosystem , Animals , Phytoplankton/metabolism , Plankton , Zooplankton/metabolism , China
20.
Nutrients ; 14(19)2022 Sep 22.
Article in English | MEDLINE | ID: mdl-36235582

ABSTRACT

Diabetes is called a "wasting and thirsting disorder" in Chinese traditional medicine because there is a depletion of vital substances in the body independent of the intake of food or water and an inability to reintroduce fluids through drinking. Pueraria lobata (Willd.) Ohwi (GG) and Pueraria thomsonii Benth. (FG) are traditional Chinese herbal medicines used in the treatment of wasting-thirst that reduce blood glucose levels. Flavonoids are the main pharmacodynamic components of GG and FG, and they are also the most studied components at present, but polysaccharides are also active components of GG and FG, which, however, are less studied. Therefore, this study aimed to investigate the effect of Pueraria polysaccharides (GG and FG polysaccharides) on type 2 diabetes (T2D), as well as their related mechanisms of action in terms of both intestinal flora and metabolomics. The C57BL/KsJ-db/db mouse model, a well-established model of obesity-induced T2D, was used in this study. The metabolomic analysis showed that Pueraria polysaccharides improved the metabolic profile of diabetic mice and significantly regulated metabolites and metabolic pathways. Both GG and FG polysaccharides regulated insulin resistance in mice by regulating PPAR signaling pathway so as to treat T2D. Additionally, Pueraria polysaccharides regulated the structure of gut microbiota and improved the diabetes-related metabolic pathway. Therefore, this study discovered the antidiabetic effects and potential mechanisms of Pueraria polysaccharides through multiple pathways involving gut microbiota and metabolites, providing a theoretical basis for further studies on their effects in the treatment of T2D.


Subject(s)
Diabetes Mellitus, Experimental , Diabetes Mellitus, Type 2 , Plant Preparations , Pueraria , Animals , Blood Glucose , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 2/drug therapy , Flavonoids , Hypoglycemic Agents/pharmacology , Mice , Mice, Inbred C57BL , Peroxisome Proliferator-Activated Receptors , Plant Preparations/pharmacology , Polysaccharides/pharmacology , Pueraria/chemistry
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