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1.
Nano Lett ; 24(28): 8642-8649, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-38976834

ABSTRACT

Two-dimensional (2D) hybrid organic-inorganic metal halide perovskites offer enhanced stability for perovskite-based applications. Their crystal structure's soft and ionic nature gives rise to strong interaction between charge carriers and ionic rearrangements. Here, we investigate the interaction of photogenerated electrons and ionic polarizations in single-crystal 2D perovskite butylammonium lead iodide (BAPI), varying the inorganic lamellae thickness in the 2D single crystals. We determine the directionality of the transition dipole moments (TDMs) of the relevant phonon modes (in the 0.3-3 THz range) by the angle- and polarization-dependent THz transmission measurements. We find a clear anisotropy of the in-plane photoconductivity, with a ∼10% reduction along the axis parallel with the transition dipole moment of the most strongly coupled phonon. Detailed calculations, based on Feynman polaron theory, indicate that the anisotropy originates from directional electron-phonon interactions.

2.
Chemphyschem ; : e202300961, 2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38850107

ABSTRACT

Efficient nitrogen (N2) fixation and activation under mild conditions are crucial for modern society. External electric fields (Felectric) can significantly affect N2 activation. In this work, the effect of Felectric on N2 activation by Nb3 clusters supported in a sumanene bowl was studied by density functional theory calculations. Four typical systems at different stages of N-N activation were studied, including two intermediates and two transition states. The impact of Felectric on various properties related to N2 activation was investigated, including the N-N bond length, overlap population density of states (OPDOS), total energy of the system, adsorption energy of N2, decomposition of energy changes, and electron transfer. The sumanene not only functions as a support and protective substrate, but also serves as a donor or acceptor under different Felectric conditions. Negative Felectric is beneficial to N-N bond activation because it promotes electron transfer to the N-N region and improves the d-π* orbital hybridization between metals and N2 in the activation process. Positive Felectric improves d-π* orbital hybridization only when the N-N is nearly dissociated. The microscopic mechanism of Felectric's effects provides insight into N2 activation and theoretical guidance for the design of catalytic reaction conditions for nitrogen reduction reactions (NRR).

3.
Micromachines (Basel) ; 15(5)2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38793149

ABSTRACT

Tungsten (W) film is increasingly utilized in various microheater applications due to its numerous advantages. These advantages include a high melting point, positive constant temperature coefficient of resistance (TCR), good mechanical stability, and compatibility with semiconductor processes. In this paper, deposition parameters for enhancing the properties of W film were investigated, and an optimized microheater was fabricated. It was found that the deposition temperature and pressure can modify the TCR to be negative or positive and the crystalline phase of W films to be alpha phases or mixed with beta phases. A W film deposited under 650 °C with a pressure of 1 pa has a positive TCR and pure alpha phase crystalline structure. We applied this optimized W film as a microheater in an RF phase-change switch (RFPCS), and the maximum voltage of the optimized W microheater increased by at least 48% in this work. By optimizing the microheater, the phase-change switch can be successfully actuated in both on and off states, demonstrated by the Raman results of the phase-change material. A voltage pulse of 20 V/200 ns was enough to turn the switch off with MΩ, and 11 V/3 µs could turn the switch on with 138 Ω. The optimized microheater and device can cycle 500 times without failure. The insertion loss and isolation of the device at 20 GHz was 1.0 dB and 22 dB.

4.
Chemosphere ; 358: 142192, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38701862

ABSTRACT

Current human health risk assessments of soil arsenic (As) contamination rarely consider bioaccessibility (IVBA), which may overestimate the health risks of soil As. The IVBA of As (As-IVBA) may differ among various soil types. This investigation of As-IVBA focused As from geological origin in a typical subtropical soil, lateritic red soil, and its risk control values. The study used the SBRC gastric phase in vitro digestion method and As speciation sequential extraction based upon phosphorus speciation extraction method. Two construction land sites (CH and HD sites) in the Pearl River Delta region were surveyed. The results revealed a high content of residual As (including scorodite, mansfieldite, orpiment, realgar, and aluminum arsenite) in the lateritic red soils at both sites (CH: 84.9%, HD: 91.7%). The content of adsorbed aluminum arsenate (CH: 3.24%, HD: 0.228%), adsorbed ferrum arsenate (CH: 8.55%, HD: 5.01%), and calcium arsenate (CH: 7.33%, HD: 3.01%) were found to be low. The bioaccessible As content was significantly positively correlated with the As content in adsorbed aluminum arsenate, adsorbed ferrum arsenate, and calcium arsenate. A small portion of these sequential extractable As speciation could be absorbed by the human body (CH: 14.9%, HD: 3.16%), posing a certain health risk. Adsorbed aluminum arsenate had the highest IVBA, followed by calcium arsenate, and adsorbed ferrum arsenate had the lowest IVBA. The aforementioned speciation characteristics of As from geological origin in lateritic red soil contributed to its lower IVBA compared to other soils. The oxidation state of As did not significantly affect As-IVBA. Based on As-IVBA, the carcinogenic and non-carcinogenic risks of soil As in the CH and HD sites decreased greatly in human health risk assessment. The results suggest that As-IVBA in lateritic red soil should be considered when assessing human health risks on construction land.


Subject(s)
Arsenic , Soil Pollutants , Soil , Arsenic/analysis , Arsenic/chemistry , Humans , Soil Pollutants/analysis , Soil Pollutants/chemistry , Risk Assessment , Soil/chemistry , Environmental Monitoring , Biological Availability , China
5.
Ying Yong Sheng Tai Xue Bao ; 35(3): 577-586, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38646744

ABSTRACT

The analytical equation based on Monin-Obukhov (M-O) similarity theory (i.e., wind profile equation) has been adopted since 1970s for using in the prediction of wind vertical profile over flat terrains, which is mature and accurate. However, its applicability over complex terrains remains unknown. This applicability signifies the accuracy of the estimations of aerodynamic parameters for the boundary layer of non-flat terrain, such as zero-displacement height (d) and aerodynamic roughness length (z0), which will determine the accuracy of frequency correction and source area analysis in calculating carbon, water, and trace gas fluxes based on vorticity covariance method. Therefore, the validation of wind profile model in non-flat terrain is the first step to test whether the flux model needs improvement. We measured three-dimensional wind speed data by using the Ker Towers (three towers in a watershed) at Qingyuan Forest CERN in the Mountainous Region of east Liaoning Province, and compared them with data from Panjin Agricultural Station in the Liaohe Plain, to evaluate the applicability of a generalized wind profile model based on the Monin-Obukhov similarity theory on non-flat terrain. The results showed that the generalized wind profile model could not predict wind speeds accurately of three flux towers separately located in different sites, indicating that wind profile model was not suitable for predicting wind speeds in complex terrains. In the leaf-off and leaf-on periods, the coefficient of determination (R2) between observed and predicted wind speeds ranged from 0.12 to 0.30. Compared to measured values, the standard error of the predicted wind speeds was high up to 2 m·s-1. The predicted wind speeds were high as twice as field-measured wind speed, indicating substantial overestimation. Nevertheless, this model correctly predicted wind speeds in flat agricultural landscape in Panjin Agricultural Station. The R2 between observed wind speeds and predicted wind speed ranged from 0.90 to 0.93. The standard error between observed and predicted values was only 0.5 m·s-1. Results of the F-test showed that the root-mean-square error of the observed and predicted wind speeds in each secondary forest complex terrain was much greater than that in flat agricultural landscape. Terrain was the primary factor affecting the applicability of wind profile model, followed by seasonality (leaf or leafless canopy). The wind profile model was not applicable to the boundary-layer flows over forest canopies in complex terrains, because the d was underestimated or both the d and z0 were underestimated, resulting in inaccurate estimation of aerodynamic height.


Subject(s)
Forests , Models, Theoretical , Wind , China , Trees/growth & development , Environmental Monitoring/methods , Ecosystem , Altitude
6.
Environ Pollut ; 349: 123927, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38582184

ABSTRACT

The recovery phase of mangrove seedlings in coastal wetland ecosystems can be negatively affected by exposure to external pollutants. This study aimed to investigate the impact of microplastics (MPs) influx, specifically polystyrene (PS) and polymethyl methacrylate (PMMA), on the growth of Aegiceras corniculatum seedlings and their accumulation of heavy metals (HMs). PS and PMMA significantly increased HMs accumulation (up to 21.0-548%), particularly in the roots of seedlings, compared to the control treatment (CK). Additionally, elevated activities of malondialdehyde and catalase enzymes were observed in the leaves of seedlings, while peroxidase enzyme activity decreased. Topological analysis of the root sediment microbiota coexistence network revealed that the modularization data increased from 0.69 (CK treatment) to 1.07 (PS treatment) and 5.11 (PMMA treatment) under the combined stress of MPs and HMs. This suggests that the introduction of MPs intensifies microbial modularization. The primary cause of increased HMs accumulation in plants is the MPs input, which influences the secretion of organic acids by plants and facilitates the shift of HMs in sediment to bioavailable states. Furthermore, changes in microbial clustering may also contribute to the elevated HMs accumulation in plants. This study provides valuable insights into the effects of external pollutants on mangrove seedlings and offers new perspectives for the preservation and restoration of mangrove coastal wetlands.


Subject(s)
Metals, Heavy , Microplastics , Seedlings , Water Pollutants, Chemical , Wetlands , Metals, Heavy/metabolism , Water Pollutants, Chemical/metabolism , Seedlings/metabolism , Microplastics/metabolism , Environmental Monitoring/methods , Primulaceae/metabolism , Geologic Sediments/chemistry
7.
Sci Total Environ ; 926: 171809, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38513845

ABSTRACT

Soil cadmium (Cd) can affect crop growth and food safety, and through the enrichment in the food chain, it ultimately poses a risk to human health. Reducing the re-mobilization of Cd caused by the release of protons and acids by crops and microorganisms after stabilization is one of the significant technical challenges in agricultural activities. This study aimed to investigate the re-mobilization of stabilized Cd within the clay mineral-bound fraction of soil and its subsequent accumulation in crops utilizing nitrogen ammonium nitrogen (NH4+-N) and nitrate nitrogen (NO3--N), at 60 and 120 mg kg-1. Furthermore, the study harvested root exudates at various growth stages to assess their direct influence on the re-mobilization of stabilized Cd and to evaluate the indirect effects mediated by soil microorganisms. The results revealed that, in contrast to the NO3--N treatment, the NH4+-N treatment significantly enhanced the conversion of clay mineral-bound Cd in the soil to NH4NO3-extractable Cd. It also amplified the accumulation of Cd in edible amaranth, with concentrations in roots and shoots rising from 1.7-6.0 mg kg-1 to 4.3-9.8 mg kg-1. The introduction of NH4+-N caused a decrease in the pH value of the rhizosphere soil and stimulated the production and secretion organic and amino acids, such as oxalic acid, lactic acid, stearic acid, succinic acid, and l-serine, from the crop roots. Furthermore, compared to NO3--N, the combined interaction of root exudates with NH4+-N has a more pronounced impact on the abundance of microbial genes associated with glycolysis pathway and tricarboxylic acid cycle, such as pkfA, pfkB, sucB, sucC, and sucD. The effects of NH4+-N on crops and microorganisms ultimately result in a significant increase in the re-mobilization of stabilized Cd. However, the simulated experiments showed that microorganisms only contribute to 3.8-6.6 % of the re-mobilization of clay mineral-bound Cd in soil. Therefore, the fundamental strategy to inhibit the re-mobilization of stabilized Cd in vegetable cultivation involves the regulation of proton and organic acid secretion by crops.


Subject(s)
Soil Pollutants , Soil , Humans , Soil/chemistry , Cadmium/analysis , Clay , Nitrogen/metabolism , Organic Chemicals/metabolism , Crops, Agricultural/metabolism , Minerals/metabolism , Fertilization , Soil Pollutants/analysis
8.
Micromachines (Basel) ; 15(3)2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38542627

ABSTRACT

The global demand for radio frequency (RF) modules and components has grown exponentially in recent decades. RF switches are the essential unit in RF front-end and reconfigurable systems leading to the rapid development of novel and advanced switch technology. Germanium telluride (GeTe), as one of the Chalcogenide phase-change materials, has been applied as an RF switch due to its low insertion loss, high isolation, fast switching speed, and low power consumption in recent years. In this review, an in-depth exploration of GeTe film characterization is presented, followed by a comparison of the device structure of directly heated and indirectly heated RF phase-change switches (RFPCSs). Focusing on the prototypical structure of indirectly heated RFPCSs as the reference, the intrinsic properties of each material layer and the rationale behind the material selection is analyzed. Furthermore, the design size of each material layer of the device and its subsequent RF performance are summarized. Finally, we cast our gaze toward the promising future prospects of RFPCS technology.

9.
Environ Pollut ; 345: 123505, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38325515

ABSTRACT

After cadmium (Cd) immobilization remediation in contaminated farmland soil, which forms of nitrogen fertilizer should be implemented to keep its sustainability? Urea and nitrate were used to compare for their effects on the remobilization of stabilized Cd in the rhizosphere soil of edible amaranth at nitrogen concentrations of 60, 95, and 130 mg kg-1. The results showed that compared to nitrate nitrogen, the Cd content in shoots increased by 76.2%, 65.6%, and 148% after applying three different concentrations of urea, and the total remobilization amount of Cd also increased by 16.0%, 24.9%, and 14.0% respectively. Urea application promotes root secretion of citric acid, malic acid, pyruvate, and γ-aminobutyric acid, crucial in remobilizing stable Cd. The application of urea promoted the expression of genes involved in sucrose transport, glycolysis, the TCA cycle, amino acid secretion, citric acid efflux, and proton efflux. Arabidopsis heterologous expression and yeast one-hybrid assays identify critical roles of AmMATE42 and AmMATE43 in citric acid and fumaric acid efflux, with AmSTOP1 activating their transcription. Inhibition of SIZ1 expression in urea treatment reduce AmSTOP1 SUMOylation, leading to increased expression of AmMATE42 and AmMATE43 and enhanced organic acids efflux. Using edible amaranth as a model vegetable, we discovered that urea is not beneficial to preserving the sustainability of stabilized Cd during the reuse of remediated farmlands contaminated with Cd.


Subject(s)
Amaranthus , Soil Pollutants , Sulfonic Acids , Cadmium/analysis , Soil/chemistry , Nitrates/metabolism , Urea/pharmacology , Urea/metabolism , Organic Chemicals/metabolism , Amaranthus/metabolism , Nitrogen/pharmacology , Nitrogen/metabolism , Citric Acid , Soil Pollutants/analysis
10.
Biomed Pharmacother ; 172: 116154, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38306844

ABSTRACT

Vitreous replacement is a commonly employed method for treating a range of ocular diseases, including posterior vitreous detachment, complex retinal detachment, diabetic retinopathy, macular hole, and ocular trauma. Various clinical substitutes for vitreous include air, expandable gas, silicone oil, heavy silicone oil, and balanced salt solution. However, these substitutes have drawbacks such as short retention time, cytotoxicity, high intraocular pressure, and the formation of cataracts, rendering them unsuitable for long-term treatment. Polymeric hydrogels possess the potential to serve as ideal vitreous substitutes due to their structure-mimicking to natural vitreous and adjustable mechanical properties. Replacement with hydrogels as the tamponade can help maintain the shape of the eyeball, apply pressure to the detached retina, and ensure the metabolic transport of substances without impairing vision. This literature review examines the required properties of artificial vitreous, including the optical properties, rheological properties, expansive force action, and physiological and biochemical functions of chemically and physically crosslinked hydrogels. The strategies for enhancing the biocompatibility and injectability of hydrogels are also summarized and discussed. From a clinical ophthalmology perspective, this paper presents the latest developments in vitreous replacement, providing clinicians with a comprehensive understanding of hydrogel clinical applications, which offers guidance for future design directions and methodologies for hydrogel development.


Subject(s)
Cataract , Diabetic Retinopathy , Ophthalmology , Humans , Hydrogels , Eye , Polymers
11.
Environ Int ; 183: 108369, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38070437

ABSTRACT

Nitrous oxide (N2O) emission during the sewage treatment process is a serious environmental issue that requires attention. However, the N2O emission in constructed wetlands (CWs) as affected by different nitrogen forms in influents remain largely unknown. This study investigated the N2O emission profiles driven by microorganisms in CWs when exposed to two typical nitrogen sources (NH4+-N or NO3--N) along with different carbon source supply (COD/N ratios: 3, 6, and 9). The results showed that CWs receiving NO3--N caused a slight increase in total nitrogen removal (by up to 11.8 %). This increase was accomplished by an enrichment of key bacteria groups, including denitrifiers, dissimilatory nitrate reducers, and assimilatory nitrate reducers, which enhanced the stability of microbial interaction. Additionally, it led to a greater abundance of denitrification genes (e.g., nirK, norB, norC, and nosZ) as inferred from the database. Consequently, this led to a gradual increase in N2O emission from 66.51 to 486.77 ug-N/(m2·h) as the COD/N ratio increased in CWs. Conversely, in CWs receiving NH4+-N, an increasing influent COD/N ratio had a negative impact on nitrogen biotransformation. This resulted in fluctuating trend of N2O emissions, which decreased initially, followed by an increase at later stage (with values of 122.87, 44.00, and 148.59 ug-N/(m2·h)). Furthermore, NH4+-N in the aquatic improved the nitrogen uptake by plants and promoted the production of more root exudates. As a result, it adjusted the nitrogen-transforming function, ultimately reducing N2O emissions in CWs. This study highlights the divergence in microbiota succession and nitrogen transformation in CWs induced by nitrogen form and COD/N ratio, contributing to a better understanding of the microbial mechanisms of N2O emission in CWs with NH4+-N or NO3--N at different COD/N ratios.


Subject(s)
Microbiota , Nitrous Oxide , Nitrous Oxide/metabolism , Denitrification , Wetlands , Nitrogen , Nitrates
12.
Mater Horiz ; 11(3): 688-699, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-37990914

ABSTRACT

The development of potent pseudocapacitive charge storage materials has emerged as an effective solution for closing the gap between high-energy density batteries and high-power density and long-lasting electrical double-layer capacitors. Sulfonyl compounds are ideal candidates owing to their rapid and reversible redox reactions. However, structural instability and low electrical conductivity hinder their practical application as electrode materials. This work addresses these challenges using a fast and clean laser process to interconnect sulfonated carbon nanodots into functionalized porous carbon frameworks. In this bottom-up approach, the resulting laser-converted three-dimensional (3D) turbostratic carbon foams serve as high-surface-area, conductive scaffolds for redox-active sulfonyl groups. This design enables efficient faradaic processes using pendant sulfonyl groups, leading to a high specific capacitance of 157.6 F g-1 due to the fast reversible redox reactions of sulfonyl moieties. Even at 20 A g-1, the capacitance remained at 78.4% due to the uniform distribution of redox-active sites on the graphitic domains. Additionally, the 3D-tsSC300 electrode showed remarkable cycling stability of >15 000 cycles. The dominant capacitive processes and kinetics were analysed using extensive electrochemical characterizations. Furthermore, we successfully used 3D-tsSC300 in flexible solid-state supercapacitors, achieving a high specific capacitance of up to 17.4 mF cm-2 and retaining 91.6% of the initial capacitance after 20 000 cycles of charge and discharge coupled with 90° bending tests. Additionally, an as-assembled flexible all-solid-state symmetric supercapacitor exhibits a high energy density of 12.6 mW h cm-3 at a high power density of 766.2 W cm-3, both normalized by the volumes of the full device, which is comparable or better than state-of-the-art commercial pseudocapacitors and hybrid capacitors. The integrated supercapacitor provides a wide potential window of 2.0 V using a serial circuit, showing great promise for metal-free energy storage devices.

13.
Ecotoxicol Environ Saf ; 267: 115657, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37924800

ABSTRACT

Soil heavy metal contamination and salinity constitute a major environmental problem worldwide. The affected area and impact of these problems are increasing day by day; therefore, it is imperative to restore their potential using environmentally friendly technology. Plant growth-promoting rhizobacteria (PGPR) provides a better option in this context. Thirty-seven bacteria were isolated from the rhizosphere of maize cultivated in metal- and salt-affected soils. Some selected bacterial strains grew well under a wide range of pH (4-10), salt (5-50 g/L), and Cd (50-1000 mg/L) stress. Three bacterial strains, Exiguobacterium aestuarii (UM1), Bacillus cereus (UM8), and Bacillus megaterium (UM35), were selected because of their robust growth and high tolerance to both stress conditions. The bacterial strains UM1, UM8, and UM35 showed P-solubilization, whereas UM8 and UM35 exhibited 1-aminocyclopropane-1-carboxylate deaminase activity and indole acetic acid (IAA) production, respectively. The bacterial strains were inoculated on Brassica juncea plants cultivated in Cd and salt-affected soils due to the above PGP activities and stress tolerance. Plants inoculated with the bacterial strains B. cereus and B. megaterium significantly (p < 0.05) increased shoot fresh weight (17 ± 1.17-29 ± 0.88 g/plant), shoot dry weight (2.50 ± 0.03-4.40 ± 0.32 g/plant), root fresh weight (7.30 ± 0.58-13.30 ± 0.58 g/plant), root dry weight (0.80 ± 0.04-2.00 ± 0.01 g/plant), and shoot K contents (62.76 ± 1.80-105.40 ± 1.15 mg/kg dwt) in normal and stressful conditions. The bacterial strain B. megaterium significantly (p < 0.05) decreased shoot Na+ and Cd++ uptake in single and dual stress conditions. Both bacterial strains, E. aestuarii and B. cereus, efficiently reduced Cd++ translocation and bioaccumulation in the shoot. Bacterial inoculation improved the uptake of K+ and Ca++, while restricted Na+ and Cd++ in B. juncea shoots indicated their potential to mitigate the dual stresses of salt and Cd in B. juncea through ion homeostasis.


Subject(s)
Bacillus megaterium , Mustard Plant , Cadmium/toxicity , Plants , Salt Tolerance , Homeostasis , Soil , Soil Microbiology , Plant Roots
14.
Environ Sci Pollut Res Int ; 30(50): 108917-108927, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37755597

ABSTRACT

To remediate historically polluted sites before their land-use changes, it is essential to understand the concentration distribution, geochemical fraction, and migratory behavior of As in soil with varied particle sizes for the use of a sieving procedure. This study investigated the amount and percentage of As in soil with different particle sizes (0.25, 0.25-1, and 1-2 mm) as well as its toxicity characteristic in leaching procedure at four previously contaminated sites in the Beijiang River Basin, South China. The results showed that the total As concentration in the collected soils ranged from 70.1 to 402.8 mg/kg, and only a few percent of soil particle samples had As contents below the local risk threshold value of 60 mg/kg. The amorphous hydrous oxide bound, crystalline hydrous oxide bound, and residual fractions (F3-F5) of the geochemical fraction of As in soil of polluted sites accounted for 82.2-95.7% of the total As distribution. However, the concentration of As in non-specifically bound fractions increased with the mass ratio of soil with coarse particle sizes due to the negative correlation of Fe-bearing minerals concentration with the mass ratio of soil with coarse particle size. According to redundancy analysis, soil with coarse particle sizes and non-specifically bound As were mostly responsible for the As concentration in the leachate. These findings confirmed that a sieving process was not suitable for the remediation of soil As at four historically contaminated sites in the Beijiang River Basin due to the high concentration of As in soil and non-negligible environmental risk of labile extractable As in soil with coarse particle size.


Subject(s)
Arsenic , Soil Pollutants , Arsenic/analysis , Rivers , Environmental Pollution/analysis , Soil/chemistry , Oxides/analysis , China , Soil Pollutants/analysis
15.
J Hazard Mater ; 458: 131922, 2023 09 15.
Article in English | MEDLINE | ID: mdl-37379599

ABSTRACT

The enhancement of cadmium (Cd) extraction by plants from contaminated soils associated with phosphate-solubilizing bacteria (PSB) has been widely reported, but the underlying mechanism remains scarcely, especially in Cd-contaminated saline soils. In this study, a green fluorescent protein-labeled PSB, the strain E. coli-10527, was observed to be abundantly colonized in the rhizosphere soils and roots of halophyte Suaeda salsa after inoculation in saline soil pot tests. Cd extraction by plants was significantly promoted. The enhanced Cd phytoextraction by E. coli-10527 was not solely dependent on bacterial efficient colonization, but more significantly, relied on the remodeling of rhizosphere microbiota, as confirmed by soil sterilization test. Taxonomic distribution and co-occurrence network analyses suggested that E. coli-10527 strengthened the interactive effects of keystone taxa in the rhizosphere soils, and enriched the key functional bacteria that involved in plant growth promotion and soil Cd mobilization. Seven enriched rhizospheric taxa (Phyllobacterium, Bacillus, Streptomyces mirabilis, Pseudomonas mirabilis, Rhodospirillale, Clostridium, and Agrobacterium) were obtained from 213 isolated strains, and were verified to produce phytohormone and promote soil Cd mobilization. E. coli-10527 and those enriched taxa could assemble as a simplified synthetic community to strengthen Cd phytoextraction through their synergistic interactions. Therefore, the specific microbiota in rhizosphere soils enriched by the inoculated PSB were also the key to intensifying Cd phytoextraction.


Subject(s)
Chenopodiaceae , Soil Pollutants , Cadmium/metabolism , Soil , Salt-Tolerant Plants/metabolism , Escherichia coli/metabolism , Soil Pollutants/metabolism , Biodegradation, Environmental , Soil Microbiology , Bacteria/metabolism , Rhizosphere , Phosphates/analysis
16.
Materials (Basel) ; 16(7)2023 Apr 03.
Article in English | MEDLINE | ID: mdl-37049148

ABSTRACT

A modified precipitation method was used to prepare yttria powers for the fabrication of yttria ceramics in this study. The precipitation behavior, phase evolution, and shape of the yttria precursor were all examined in the presence or absence of an electric field. The findings demonstrate that the phases of the yttria precursor were Y2(CO3)3·2H2O with and without an electric field, while the morphology changed from flake to needle-like under the action of the electric field. After calcining both yttria precursors at 750 °C, yttria powders with similar morphologies were obtained and then densified via conventional sintering (CS) and spark plasma sintering (SPS). The densification and thermal shock resistance of the yttria ceramics were investigated. The yttria ceramics sintered using SPS had higher bulk density and thermal shock resistance than the samples sintered using CS. When the sintering process for the ceramics sintered from needle-like yttria powder was switched from CS to SPS, the bulk density increased from 4.44 g·cm-3 to 5.01 g·cm-3, while the number of thermal shock tests increased from two to six. The denser samples showed better thermal shock resistance, which may be related to the fracture mechanism shifting from intergranular fracture to transgranular fracture.

17.
Polymers (Basel) ; 15(3)2023 Jan 24.
Article in English | MEDLINE | ID: mdl-36771907

ABSTRACT

Continuous fiber-reinforced composite 3D printing (CFRC 3DP) has become a hot topic of interest for many experts and scholars. Continuous fiber-reinforced prepreg filament (CFRPF) for printing needs to be prepared in advance. In this paper, on the basis of the resin fusion impregnation theory, a fabrication device was designed for continuous carbon fiber-reinforced polycarbonate prepreg filament (CCFRPF). Then, according to the orthogonal test and the TOPSIS entropy weight optimization theory, the optimization method for CFRPF/PC preparation process parameters was proposed, and the relationship between the preparation process parameters and the performance indexes was discussed. The results show that when preparing CCFRPF/PC, the weight of diameter performance index is the largest, about 0.75. The optimal combination of process parameters for CCFRPF/PC is, respectively, 285 °C for the outlet mold temperature, 305 °C for the impregnation mold temperature, and 1 m/min for the winding speed. In this case, the diameter, roundness, minimum curvature radius and tensile strength of 0.375 mm, 29.4 µm, 9.775 mm and 1298 MPa were achieved, respectively.

18.
J Stroke Cerebrovasc Dis ; 32(3): 106950, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36542891

ABSTRACT

OBJECTIVES: The impairment of activities of daily living (ADL) has brought a heavy burden to the life of patients after stroke. Timely and accurate assessment of patients' activities of daily living is very necessary, which determines the whole process of diagnosis, rehabilitation and prognosis of patients. However, the patients with limited mobility or transportation are difficulted to gain high quality assessment services. This study aimed to explore the reliability of remote Longshi Assessment Scale of Activities of Daily Life (Longshi Scale) with smartphone video calls by comparing the consistency of remote assessment and bedside assessment, as well as the test-retest reliability of the remote assessment. The evaluation duration of these two methods was recorded and the level of satisfaction of patients was investigated. METHODS: In this prospective study, a total of 129 stroke survivors were recruited and accepted a bedside face-to-face assessment and a remote assessment by video calls. The Longshi Scale was used for both bedside and remote assessment and conducted with the inquiry between patients and evaluators. A satisfaction questionnaire was also launched. RESULTS: The result of disability level evaluated from the bedside and remote assessments was highly consistent. The intraclass correlation coefficient with weighted kappa (wK) value was 0.86 (95% confidence interval, 0.80∼0.92). And test-retest of the remote assessment indicated an excellent agreement beyond chance, and its correlation coefficient with wK value was 0.96 (95% confidence interval, 0.92∼1.00). It took 74.44±55.3 s to complete the bedside assessment and 90.86±63.30 s to complete the remote assessment of Longshi Scale. There was no statistical significance in the assessment duration between these two methods (P = 0.056). Satisfaction surveys showed more than 85% of participants were satisfied or very satisfied with remote Longshi scale assessment. CONCLUSIONS: The remote assessment of Longshi Scale with smartphone video calls is reliable and has high acceptance. This method can be readily implemented to evaluate the ADL of stroke patients to improve the capacity of rehabilitation and health services in remote areas.


Subject(s)
Stroke Rehabilitation , Stroke , Telemedicine , Humans , Smartphone , Activities of Daily Living , Reproducibility of Results , Prospective Studies , Stroke/diagnosis , Stroke/therapy
19.
Fa Yi Xue Za Zhi ; 39(6): 601-607, 2023 Dec 25.
Article in English, Chinese | MEDLINE | ID: mdl-38228480

ABSTRACT

Age estimation based on tissues or body fluids is an important task in forensic science. The changes of DNA methylation status with age have certain rules, which can be used to estimate the age of the individuals. Therefore, it is of great significance to discover specific DNA methylation sites and develop new age estimation models. At present, statistical models for age estimation have been developed based on the rule that DNA methylation status changes with age. The commonly used models include multiple linear regression model, multiple quantile regression model, support vector machine model, artificial neural network model, random forest model, etc. In addition, there are many factors that affect the level of DNA methylation, such as the tissue specificity of methylation. This paper reviews these modeling methods and influencing factors for age estimation based on DNA methylation, with a view to provide reference for the establishment of age estimation models.


Subject(s)
DNA Methylation , Forensic Genetics , Humans , CpG Islands , Neural Networks, Computer , Linear Models , Aging/genetics
20.
Front Med (Lausanne) ; 10: 1280776, 2023.
Article in English | MEDLINE | ID: mdl-38259837

ABSTRACT

Neovascular glaucoma is a condition that results from central retinal vein occlusion and often leads to blindness. Accurate evaluation and appropriate treatment are crucial for patients. However, there is currently no uniform and clear standard to differentiate between ischemic and non-ischemic central retinal vein occlusion. Also, the assessment of neovascular glaucoma progression is uncertain. Meanwhile, although pan-retinal photocoagulation is a standard treatment to prevent the onset of neovascular glaucoma, its actual efficacy and the timing of intervention remain highly controversial. It is still challenging to balance the risks of side effects in the visual field against the uncertain effectiveness of the treatment. This paper delves into the pathogenesis of neovascular glaucoma to understand the development of therapeutic approaches. By taking into account various assessment criteria of central retinal vein occlusion and neovascular glaucoma over the years, combining functional tests and morphological tests provides the most accurate and rigorous solution. The age of patients, the extent, location, and duration of retinal ischemia are the primary factors that affect the severity and extent of ischemic central retinal vein occlusion and induce serious complications. From the perspective of prevention and treatment, the ischemic index is closely related to the development of neovascularization. The paper provides essential insights into the mechanism, efficacy, complications, and optimal timing of pan-retinal photocoagulation. Comparing the treatment effects of pan-retinal photocoagulation and intravitreal anti-VEGF injections, we suggest a combination of both treatments to explore effective treatment with fewer side effects in the long term. This article details the debate on the above issues and explores ideas for the clinical diagnosis and preventive treatment of neovascular glaucoma that results from ischemic central retinal vein occlusion.

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