| 1. |
- Jia, Xiaomin, et al.
(författare)
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Single crystal metal-organic framework constructed by vertically self-pillared nanosheets and its derivative for oriented lithium plating
- 2021
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Ingår i: Cuihuà xuébào. - : Elsevier BV. - 0253-9837 .- 1872-2067. ; 42:9, s. 1553-1560
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Tidskriftsartikel (refereegranskat)abstract
- This vertically self-pillared (VSP) structure extends the application range of traditional porous materials with facile mass/ion transport and enhanced reaction kinetics. Here, we prepare a single crystal metal-organic framework (MOF), employing the ZIF-67 structure as a proof of concept, which is constructed by vertically self-pillared nanosheets (VSP-MOF). We further converted VSP-MOF into VSP-cobalt sulfide (VSP-CoS2) through a sulfidation process. Catalysis plays an important role in almost all battery technologies; for metallic batteries, lithium anodes exhibit a high theoretical specific capacity, low density, and low redox potential. However, during the half-cell reaction (Li++e=Li), uncontrolled dendritic Li penetrates the separator and solid electrolyte interphase layer. When employed as a composite scaffold for lithium metal deposition, there are many advantage to using this framework: 1) the VSP-CoS2 substrate provides a high specific surface area to dissipate the ion flux and mass transfer and acts as a pre-catalyst, 2) the catalytic Co center favors the charge transfer process and preferentially binds the Li+ with the enhanced electrical fields, and 3) the VSP structure guides the metallic propagation along the nanosheet 2D orientation without the protrusive dendrites. All these features enable the VSP structure in metallic batteries with encouraging performances.
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| 2. |
- Ma, Zhaoying, et al.
(författare)
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Mineralogical and magnetic variations of periglacial loess in SE Tibet reveal mid-Pleistocene expansion of Tibetan glacial activity
- 2024
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Ingår i: Quaternary Science Reviews. - : Elsevier. - 0277-3791 .- 1873-457X. ; 330
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Tidskriftsartikel (refereegranskat)abstract
- The formation and evolution of the cryosphere on the Tibetan Plateau is of great significance in understanding the Earth's carbon and climatic system. Periglacial loess deposits in southeastern Tibet offer a means to constrain this history as they contain critical information on glacial grinding and frost shattering processes in high-altitude mountain regions through time, which yield lithogenic fractions of largely loess silts and sands. Based on combined analyses of lithogenic magnetic properties and mineralogical composition, here we find that increasing high mountain production and supply of fresh detrital components since the mid-Pleistocene climate transition (MPT, 1.2–0.7 Ma) led to a substantial increase of the lithogenic susceptibility and decrease in chemical weathering intensity of periglacial loess in southeastern Tibet. The agreement of these findings with similar results from eolian loess on the northern margins of the Tibetan Plateau suggests a plateau-wide glacier expansion during the MPT. Enhanced glacial erosion and freeze-thaw activities occurred in the high-altitude mountain regions of the plateau during the MPT, thereby providing vast amounts of fresh detritus for the formation of loess deposits. High and constant values of lithogenic magnetic parameters in the loess deposits after 0.7–0.6 Ma further indicate that the Middle Pleistocene is a critical period for the establishment of modern-like glacial and periglacial landforms on the Tibetan Plateau. Our results further suggest that enhanced Quaternary glaciation in SE Tibet occurred earlier than in the north, which we attribute to climate cooling combined with regional seasonal snowline lowering. As such, a close relationship exists between global climate changes, development of pan-Tibetan glaciations, and large-scale dust emission.
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| 3. |
- Xing, Yi, et al.
(författare)
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Integrated opposite charge grafting induced ionic-junction fiber
- 2023
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Ingår i: Nature Communications. - : NATURE PORTFOLIO. - 2041-1723. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- The emergence of ionic-junction devices has attracted growing interests due to the potential of serving as signal transmission and translation media between electronic devices and biological systems using ions. Among them, fiber-shaped iontronics possesses a great advantage in implantable applications owing to the unique one-dimensional geometry. However, fabricating stable ionic-junction on curved surfaces remains a challenge. Here, we developed a polyelectrolyte based ionic-junction fiber via an integrated opposite charge grafting method capable of large-scale continuous fabrication. The ionic-junction fibers can be integrated into functions such as ionic diodes and ionic bipolar junction transistors, where rectification and switching of input signals are implemented. Moreover, synaptic functionality has also been demonstrated by utilizing the fiber memory capacitance. The connection between the ionic-junction fiber and sciatic nerves of the mouse simulating end-to-side anastomosis is further performed to realize effective nerve signal conduction, verifying the capability for next-generation artificial neural pathways in implantable bioelectronics. Ionic-junction devices are difficult to integrate with fiber-shaped tissues like nerves and muscles for applications in implantable bioelectronics due to their large size and bulk structure. Authors realize here easy to implant fiber-shaped iontronics through an integrated opposite charge grafting process, enabling the construction of ionic logic gates and artificial neural pathways.
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| 4. |
- Zhang, Xiao, et al.
(författare)
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Heparanase overexpression impedes perivascular clearance of amyloid-beta from murine brain : relevance to Alzheimer's disease
- 2021
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Ingår i: Acta neuropathologica communications. - : BioMed Central (BMC). - 2051-5960. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Defective amyloid-beta (A beta) clearance from the brain is a major contributing factor to the pathophysiology of Alzheimer's disease (AD). A beta clearance is mediated by macrophages, enzymatic degradation, perivascular drainage along the vascular basement membrane (VBM) and transcytosis across the blood-brain barrier (BBB). AD pathology is typically associated with cerebral amyloid angiopathy due to perivascular accumulation of A beta. Heparan sulfate (HS) is an important component of the VBM, thought to fulfill multiple roles in AD pathology. We previously showed that macrophage-mediated clearance of intracortically injected A beta was impaired in the brains of transgenic mice overexpressing heparanase (Hpa-tg). This study revealed that perivascular drainage was impeded in the Hpa-tg brain, evidenced by perivascular accumulation of the injected A beta in the thalamus of Hpa-tg mice. Furthermore, endogenous A beta accumulated at the perivasculature of Hpa-tg thalamus, but not in control thalamus. This perivascular clearance defect was confirmed following intracortical injection of dextran that was largely retained in the perivasculature of Hpa-tg brains, compared to control brains. Hpa-tg brains presented with thicker VBMs and swollen perivascular astrocyte endfeet, as well as elevated expression of the BBB-associated water-pump protein aquaporin 4 (AQP4). Elevated levels of both heparanase and AQP4 were also detected in human AD brain. These findings indicate that elevated heparanase levels alter the organization and composition of the BBB, likely through increased fragmentation of BBB-associated HS, resulting in defective perivascular drainage. This defect contributes to perivascular accumulation of A beta in the Hpa-tg brain, highlighting a potential role for heparanase in the pathogenesis of AD.
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| 5. |
- Hao, Qian, et al.
(författare)
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Soil silicon fractions along karst hillslopes of southwestern China
- 2022
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Ingår i: Journal of Soils and Sediments. - : Springer Nature. - 1439-0108 .- 1614-7480. ; 22, s. 1121-1134
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Tidskriftsartikel (refereegranskat)abstract
- Purpose The karst region in southwestern China is undergoing soil erosion and rocky desertification. The different silicon (Si) fractions along the hillslopes in this mountainous region could benefit plant growth and alleviate the ecological deterioration. However, extensive distribution of carbonate rocks may lead to limited plant available Si. The mountainous terrain in karst region also leads to more Si output, which seriously affects the biogeochemical cycle of Si in this area. Yet, the soil Si fractions in the karst region have not been fully evaluated. Methods Soil profiles and their corresponding plants were sampled from two typical karst mountains in Guizhou, China. The different fractions of non-crystalline Si in soil, accounting for the most important pool for Si availability to plants, were analyzed by the improved sequential chemical extraction and Si concentrations in plants grown in this region were also measured. Results The concentration and storage of non-crystalline Si were higher at lower slopes (storage was 2.44, 2.73, and 3.25 kg center dot m(-2) for upper, middle, and lower slopes, respectively) than other slope positions. Grasses dominated at lower slopes and contained significantly higher Si (mean +/- SD: 14.42 +/- 6.63 mg center dot g(-1)) than trees and shrubs (1.94 +/- 1.78 and 1.29 +/- 1.00 mg center dot g(-1), respectively), which were primarily distributed on upper slopes. However, Si concentrations of the same plant species in different slope positions had no significant correlation with soil acid Na acetate-Si, the Si regarded as directly available for plants. Conclusions This study suggests that plant species and soil properties have a significant impact on the soil Si distribution of hillslopes in karst region. Soil erosion may decrease non-crystalline Si concentrations in soils and impair Si uptake in grasses, which need to be considered in ecosystem management in this region.
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| 6. |
- Jiang, Ying, et al.
(författare)
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Secular Difference in Body Mass Index From 2014 to 2020 in Chinese Older Adults : A Time-Series Cross-Sectional Study
- 2022
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Ingår i: Frontiers in Nutrition. - : Frontiers Media SA. - 2296-861X. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Background: Body mass index (BMI) is the most widely used parameter to assess the body weight status. Both the increase of BMI (overweight and obesity) and decrease of BMI (underweight) has been associated with high risk of adverse outcome, such as stroke, disability, and even death. However, recent data on secular differences in BMI in the Chinese aged population are limited. The present study provides robust new evidence about the evolving epidemic of obesity among aged adults in China.Objective: Evaluating secular difference in BMI in a group of Chinese older adults.Materials and Methods: We analyzed 7 continuous survey years (2014–2020), including 50,192 Chinese aged participants (25,505 men and 24,687 women, aged 71.9 ± 6.1 years, age range: 65–99 years). Information on sex, age, height, and body weight, was collected based on medical history. Participants were classified into four groups: underweight (BMI < 18.5 kg/m2), normal weight (18.5 kg/m2 ≤ BMI < 25 kg/m2), overweight (25 kg/m2 ≤ BMI < 30 kg/m2), and obesity (BMI ≥ 30 kg/m2). Linear regressions were used to assess the secular difference in BMI. Sex and age differences were also evaluated by stratified analyses.Results: From 2014 to 2020, age-adjusted mean BMI increased by 0.3 kg/m2 (95% CI: 0.1, 0.5 kg/m2) in men, and 0.5 kg/m2 (95% CI: 0.2, 0.7 kg/m2) in women. Age-standardized prevalence of underweight decreased from 3.0 to 2.3% in men, and from 3.0 to 2.1% in women. Age-standardized prevalence of overweight increased in both men (from 40.1 to 41.7%) and women (from 37.8 to 39.8%), and so as obesity (men: from 4.1 to 6.1%; women: from 5.8 to 8.7%).Conclusion: Our results confirmed that BMI gradually increased from 2014 to 2020. The age-adjusted mean BMI increased by 0.3 kg/m2 in older men, and 0.5 kg/m2 in older women. The age- and sex-standardized prevalence of overweight and obesity significantly increased, especially in 70–79-year age group, while the prevalence of underweight decreased. The combination of a balanced-diet and physical exercise is needed to maintain optimal BMI range for the aged population.
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| 7. |
- Shilei, Yang, et al.
(författare)
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A review of carbon isotopes of phytoliths : implications for phytolith-occluded carbon sources
- 2020
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Ingår i: Journal of Soils and Sediments. - : Springer. - 1439-0108 .- 1614-7480. ; 20:4, s. 1811-1823
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Tidskriftsartikel (refereegranskat)abstract
- Purpose Phytolith-occluded carbon (PhytOC) is mainly derived from the products of photosynthesis, which can be preserved in soils and sediments for hundreds-to-thousands of years due to the resilient nature of the amorphous phytolith silica. Therefore, stable and radioactive carbon (C) isotopes of phytoliths can be effectively utilized in paleoecological and archeological research. However, there still exists debate about the applicability of C isotopes of phytoliths, as a “two-pool” hypothesis to characterize PhytOC sources has been proposed, whereby a component of the PhytOC is derived from soil organic matter (SOM) absorbed through plant roots. Therefore, it is necessary to review this topic to better understand the source of PhytOC. Materials and method We introduce the stable and radioactive C isotopic compositions of PhytOC, present the impacts of different extraction methods on the study of PhytOC, and discuss the implications of these factors for determining the sources of PhytOC. Results and discussion Based on this review, we suggest that organic matter synthesized by photosynthesis is the main source of PhytOC. However, it is important to make clear whether and how SOM-derived C present in phytoliths influence the controversial “too-old” skew and isotopic fractionation. Conclusions Though the two-pool hypothesis has been proved by many researches, the carbon isotopes of phytoliths still have potential in paleoecology and archeology, because the main source is photosynthesis and many previous studies put forward the availability of these parameters. This review also shows that phytolith C isotopes may vary with different organic C compounds within phytoliths, which needs further study at the molecular scale. Different phytolith extraction methods can influence 14C dating results.
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| 8. |
- Wu, Lele, et al.
(författare)
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Organic matter composition and stability in estuarine wetlands depending on soil salinity
- 2024
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Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 945
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Tidskriftsartikel (refereegranskat)abstract
- Coastal wetlands are key players in mitigating global climate change by sequestering soil organic matter. Soil organic matter consists of less stable particulate organic matter (POM) and more stable mineral-associated organic matter (MAOM). The distribution and drivers of MAOM and POM in coastal wetlands have received little attention, despite the processes and mechanisms differ from that in the upland soils. We explored the distribution of POM and MAOM, their contributions to SOM, and the controlling factors along a salinity gradient in an estuarine wetland. In the estuarine wetland, POM C and N were influenced by soil depth and vegetation type, whereas MAOM C and N were influenced only by vegetation type. In the estuarine wetland, SOM was predominantly in the form of MAOM (> 70 %) and increased with salinity (70 %–76 %), leading to long-term C sequestration. Both POM and MAOM increased with SOM, and the increase rate of POM was higher than that of MAOM. Aboveground plant biomass decreased with increasing salinity, resulted in a decrease in POM C (46 %–81 %) and N (52 %–82 %) pools. As the mineral amount and activity, and microbial biomass decreased, the MAOM C (2.5 %–64 %) and N pool (8.6 %–59 %) decreased with salinity. When evaluating POM, the most influential factors were microbial biomass carbon (MBC) and dissolved organic carbon (DOC). Key parameters, including MBC, DOC, soil salinity, soil water content, aboveground plant biomass, mineral content and activity, and bulk density, were identified as influencing factors for both MAOM abundance. Soil water content not only directly controlled MAOM, but together with salinity also indirectly regulated POM and MAOM by controlling microbial biomass and aboveground plant biomass. Our findings have important implications for improving the accumulation and increased stability of soil organic matter in coastal wetlands, considering the global sea level rise and increased frequency of inundation.
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| 9. |
- Yan, Tao, et al.
(författare)
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Diet-rich in wheat bran modulates tryptophan metabolism and AhR/IL-22 signalling mediated metabolic health and gut dysbacteriosis: A novel prebiotic-like activity of wheat bran
- 2023
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Ingår i: Food Research International. - : Elsevier BV. - 0963-9969 .- 1873-7145. ; 163
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Tidskriftsartikel (refereegranskat)abstract
- Tryptophan metabolism has shown to involve in pathogenesis of various metabolic diseases. Gut microbiota-orientated diets hold great potentials to improve metabolic health via regulating tryptophan metabolism. The present study showed that the 6-week high fat diet (HFD) disturbed tryptophan metabolism accompanied with gut dysbacteriosis, also influenced the dietary tryptophan induced changes in cecum microbiome and serum metabolome in mice. The colonic expressions of aryl hydrocarbon receptor (AhR) and interleukin-22 (IL-22) were significantly reduced in mice fed on HFD. Notably, a diet- rich in wheat bran effectively inhibited transformation of tryptophan to kynurenine-pathway metabolites, while increased melatonin and microbial catabolites, i.e. indole-3-propionic acid, indole-3-acetaldehyde and 5-hydroxy-indole-3-acetic acid. Such regulatory effects were accompanied with reduced fasting glucose and total triglycerides, and promoted AhR and IL-22 levels in HFD mice. Wheat bran increased the abundance of health promoting bacteria (e.g., Akkermansia and Lactobacillus), which were significantly correlated with tryptophan derived indolic metabolites. Additionally, beneficial modulatory effects of wheat bran on indolic metabolites in associations with gut dysbacteriosis from type 2 diabetes patients were confirmed in vitro fecal fermentation experiment. Our study proves the detrimental effects of HFD induced gut dysbacteriosis on tryptophan metabolism that may influence immune modulation, and provides novel insights in the mechanisms by which wheat bran could induce health benefits.
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