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1.
Ann Neurol ; 96(5): 970-980, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39096048

RESUMEN

OBJECTIVE: Glymphatic system is a recently discovered macroscopic waste clearance system associated with numerous neurological diseases. However, little is known about glymphatic system development in neonates. We sought to evaluate diffusion along the perivascular space (ALPS) index, a proxy for glymphatic system function, in neonates and investigate its potential associations with maturation, sex, and preterm birth. METHODS: Diffusion magnetic resonance imaging (MRI) data in 418 neonates, including 92 preterm neonates (57 males) and 326 term neonates (175 males), from the Developing Human Connectome Project were used for evaluating ALPS index. Linear regression modeling was performed to assess group differences in the ALPS index according to preterm birth and sex. Pearson's and partial correlation analysis were performed to assess the association between the ALPS index and gestational age (GA) as well as postmenstrual age (PMA) at MRI. Moderation analysis was performed to assess the moderation effect of preterm birth on the relationship between the ALPS index and PMA. RESULTS: Compared to term neonates, preterm neonates exhibited lower ALPS indices (p < 0.001). The ALPS index positively correlated with PMA (p = 0.004) and GA (p < 0.001). Preterm birth (p = 0.013) had a significant moderation effect on the relationship between the ALPS index and PMA. Sex had no significant direct effect (p = 0.639) or moderation effect (p = 0.333) on ALPS index. INTERPRETATION: Glymphatic system development is a dynamic process in neonates, which can be moderated by preterm birth, the ALPS index could serve as a sensitive biomarker for monitoring this process. ANN NEUROL 2024;96:970-980.


Asunto(s)
Encéfalo , Imagen de Difusión por Resonancia Magnética , Sistema Glinfático , Recien Nacido Prematuro , Humanos , Sistema Glinfático/diagnóstico por imagen , Masculino , Recién Nacido , Femenino , Recien Nacido Prematuro/crecimiento & desarrollo , Encéfalo/diagnóstico por imagen , Encéfalo/crecimiento & desarrollo , Imagen de Difusión por Resonancia Magnética/métodos , Edad Gestacional
2.
Radiology ; 311(3): e232274, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38888481

RESUMEN

Background The role of perivascular space (PVS) dysfunction in obstructive sleep apnea (OSA) requires further study. Purpose To compare MRI indexes of PVS across patients with differing severities of OSA and relate them with disease characteristics and treatment. Materials and Methods This single-center prospective study included healthy controls (HCs) and patients with complaints of snoring who underwent MRI and cognitive evaluation between June 2021 and December 2022. Participants with complaints of snoring were classified into four groups (snoring, mild OSA, moderate OSA, and severe OSA). PVS networks were assessed at MRI using PVS volume fraction, extracellular free water (FW), and diffusion tensor imaging analysis along the PVS (DTI-ALPS). One-way analysis of variance and Pearson correlation were used for analysis. Alterations in PVS indexes and cognitive performance after treatment were assessed in 15 participants with moderate OSA. Results A total of 105 participants (mean age, 33.4 years ± 8.9 [SD]; 80 males) and 50 HCs (mean age, 37.0 years ± 8.6; 33 males) were included. Higher mean PVS volume fraction was observed in participants with severe OSA (n = 23) than in patients with mild OSA (n = 36) (0.11 vs 0.10; P = .03). Participants with severe OSA exhibited higher mean FW index (0.11) than both HCs (0.10; P < .001) and patients with mild OSA (0.10; P = .003). All patient groups had lower DTI-ALPS than HCs (range, 1.5-1.9 vs 2.1; all P < .001). DTI-ALPS correlated with cognitive performance on the Stroop Color and Word Test (r range, -0.23 to -0.24; P value range, .003-.005). After treatment, PVS indexes changed (P value range, <.001 to .01) and cognitive performance improved (P value range, <.001 to .03). Conclusion Differences in PVS indexes were observed among participants with differing severities of OSA and HCs. Indexes correlated with measures of cognitive function, and changes in indexes and improvement in cognitive performance were observed after treatment in participants with moderate OSA. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Port in this issue.


Asunto(s)
Disfunción Cognitiva , Imagen por Resonancia Magnética , Apnea Obstructiva del Sueño , Humanos , Apnea Obstructiva del Sueño/diagnóstico por imagen , Apnea Obstructiva del Sueño/complicaciones , Masculino , Femenino , Estudios Prospectivos , Adulto , Imagen por Resonancia Magnética/métodos , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/etiología , Sistema Glinfático/diagnóstico por imagen , Imagen de Difusión Tensora/métodos , Persona de Mediana Edad
3.
J Magn Reson Imaging ; 59(2): 648-658, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37249021

RESUMEN

BACKGROUND: The promoter variant rs17111237 in the CEP128 closely relates to radiotherapy (RT)-related brain necrosis in nasopharyngeal carcinoma (NPC) patients. PURPOSE: To explore RT-related dynamic alterations in brain morphology and their potential genetic mechanism, and to explore the modulatory effects of CEP128 genetic variants on RT-related brain morphological alterations in NPC patients. STUDY TYPE: Prospective, longitudinal. POPULATION: One hundred one patients with histopathologic ally-proven NPC (age 41.64 ± 9.63, 46 male), analyzed at baseline (pre-RT), 3-months post-RT and 6 months post-RT, and 19 sex-, age- and education-matched healthy controls. FIELD STRENGTH/SEQUENCE: 3D gradient echo brain volume (3D-BRAVO) and diffusion-weighted single-shot spin-echo echo-planar sequences at 3.0 T. ASSESSMENT: rs17111237 in CEP128 was detected by Sanger sequencing. Structural and diffusion images were processed with FreeSurfer and FSL. Morphometric similarity network (MSN) was constructed with nine cortical indices derived from structural and diffusion images. STATISTICAL TESTS: One-way ANOVA, chi-square test. Pearson's correlation analysis was conducted to measure the relationship between CEP128 gene-expression level in human brain and MSN alterations. Repeated analysis of variance performed to assess group differences in MSN and the modulatory effects of the CEP128 gene within patients. Significance level: P < 0.05, false-discovery rate correction. RESULTS: RT-related significant widespread MSN alterations were observed in the cortices of NPC patients. Notably, regional MSN alterations had a weak but significant negative correlation with the cortical pattern of CEP128 gene expression (r = -0.152). Furthermore, rs17111237 in the CEP128 had significant modulatory effects on the observed MSN alterations in NPC patients, with the modulatory effects being most obvious at 3 months post-RT. CONCLUSIONS: MSN has potential to serve as a sensitive biomarker to detect RT-related brain injury. Inter-brain regional and inter-patient variability of RT-related brain injuries may be attributed to the cortical expression of the CEP128 gene and the modulatory effects of the promoter variant rs17111237 in CEP128. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Lesiones Encefálicas , Neoplasias Nasofaríngeas , Humanos , Masculino , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Lesiones Encefálicas/patología , Imagen por Resonancia Magnética/métodos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patología , Estudios Prospectivos
4.
J Magn Reson Imaging ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39304516

RESUMEN

BACKGROUND: Birth asphyxia (BA) and germinal matrix hemorrhage-intraventricular hemorrhage (GMH-IVH) are common clinical events in preterm neonates. However, their effects on the glymphatic system (GS) development in preterm neonates remain arcane. PURPOSE: To evaluate the developmental trajectory of the GS, and to investigate the effects of BA and GMH-IVH on GS function in preterm neonates. STUDY TYPE: Prospective. POPULATION: Two independent datasets, prospectively acquired internal dataset (including 99 preterm neonates, 40 female, mean [standard deviation] gestational age (GA) at birth, 29.95 [2.63] weeks) and the developing Human Connectome Project (dHCP) dataset (including 81 preterm neonates, 29 female, median [interquartile range] GA at birth, 32.71 [4.28] weeks). FIELD STRENGTH/SEQUENCE: 3.0 T MRI and diffusion-weighted spin-echo planar imaging sequence. ASSESSMENT: The diffusion-weighted images were preprocessed in volumetric space using the FMRIB Software Library and diffusion along the perivascular space (DTI-ALPS) index was accessed to evaluate GS function. STATISTICAL TESTS: Two sample t tests, one-way analysis of variance followed by least-significant difference (LSD) post hoc analysis, chi-squared tests, and Pearson's correlation analysis. Significance level: P < 0.05. RESULTS: In prospectively acquired internal dataset, preterm neonates with BA exhibited a significant lower DTI-ALPS index than those without BA (0.98 ± 0.08 vs. 1.08 ± 0.07, T = -5.89); however, GMH-IVH did not exert significant influences on the DTI-ALPS index (P = 0.83 and 0.27). The DTI-ALPS index increased significantly at postmenstrual age ranging from 25 to 34 weeks (r = 0.38) and then plateaued after 34 weeks (P = 0.35), which we also observed in the dHCP dataset. DATA CONCLUSION: BA rather than GMH-IVH serves as the major influencing factor in the development of GS in preterm neonates. Moreover, as GS development follows a nonlinear trajectory, we recommend close monitoring of GS development in preterm neonates with a GA less than 34 weeks. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.

5.
BMC Musculoskelet Disord ; 25(1): 61, 2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-38216881

RESUMEN

BACKGROUND: Traditional Scarf osteotomy (TSO) is an effective procedure with a good record in moderate to severe hallux valgus (MSHV) surgery. In order to overcome shortcomings of TSO, Modified Rotary Scarf osteotomy (MRSO) was introduced in this study, which aimed to compare the clinical and radiological outcome in the patients treated with MRSO or TSO. METHODS: Of 175 patients (247 feet) with MSHV, 100 patients (138 feet) treated with MRSO and 75 patients (109 feet) treated with TSO were evaluated according to relevant indicators in twenty-four months follow-up. Pre-surgical and post-surgical HVA, IMA, DMAA, MTP-1 ROM, sesamoid grade and AOFAS (American Orthopaedic Foot and Ankle Society) scores and postsurgical complications were evaluated. RESULTS: Both groups manifested similar baseline characters. The mean follow-up was of 25.9 (range, 22-37) months. Significantly lower IMA, lower Sesamoid grade and higher DMAA at six months, twelve months and twenty-four months post-surgically had been showed in MRSO group compared to TSO group. There was no significant difference in HVA, MTP-1 ROM and AOFAS data at each follow-up time point post-surgically between the two groups. No major complications occurred in either group. CONCLUSION: MRSO showed comparable results to TSO, and improved IMA and sesamoid grade to a greater extent, with a lower probability of throughing effect. Although DMAA could be increased by MRSO, MRSO could still be a reproducible, non-dangerous and efficacious alternative procedure for treating HV patients which do not have severe DMAA.


Asunto(s)
Juanete , Hallux Valgus , Huesos Metatarsianos , Humanos , Hallux Valgus/diagnóstico por imagen , Hallux Valgus/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Osteotomía/efectos adversos , Osteotomía/métodos , Huesos Metatarsianos/cirugía
6.
Chaos ; 34(10)2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39413263

RESUMEN

This study presents a modified stochastic diffusion particle tracking model (MSDPTM) that incorporates energy cascade theory to more accurately simulate suspended sediment transport. The impact of turbulent eddies on sediment particles is an intermittent process, which is also considered in this study. The study examines the time correlation between eddies using eddy turnover time and finds that closer-scale eddies exhibit higher correlations than those farther apart. The statistical properties of particle movement, such as the ensemble mean and variance of particle trajectories, have been calculated and compared with the stochastic diffusion particle tracking model (SDPTM) results. Notably, MSDPTM with intermittency demonstrates a significantly larger ensemble mean of particle trajectories in the streamwise direction than other particle tracking models. The proposed model is validated through comparison with available data, showing its enhanced performance. The results of the simulation indicate that MSDPTM outperforms SDPTM, especially when the intermittency effect of eddies is considered.

7.
J Magn Reson Imaging ; 58(6): 1863-1874, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37022091

RESUMEN

BACKGROUND: Patients with hepatitis B virus-related cirrhosis (HBV-RC) exhibit progressive neurologic dysfunction from primary sensorimotor to high-order cognition, as their disease advances. However, the exact neurobiologic mechanisms and the potential association with gene-expression profiles are not fully understood. PURPOSE: To explore the hierarchical disorganization in the large-scale functional connectomes in HBV-RC patients and to investigate its potential underlying molecular basis. STUDY TYPE: Prospective. POPULATION: Fifty HBV-RC patients and 40 controls (Cohort 1) and 30 HBV-RC patients and 38 controls (Cohort 2). FIELD STRENGTH/SEQUENCE: Gradient-echo echo-planar and fast field echo sequences at 3.0 T (Cohort 1) and 1.5 T (Cohort 2). ASSESSMENT: Data were processed with Dpabi and the BrainSpace package. Gradient scores were evaluated from global to voxel level. Cognitive measurement and patients grouping were based on psychometric hepatic encephalopathy scores. The whole-brain microarray-based gene-expression data were obtained from the AIBS website. STATISTICAL TESTS: One-way ANOVA, chi-square test, two-sample t-test, Kruskal-Wallis test, Spearman's correlation coefficient (r), the gaussian random field correction, false discovery rate (FDR) correction and the Bonferroni correction. Significance level: P < 0.05. RESULTS: HBV-RC patients exhibited a robust and replicable connectome gradient dysfunction, which was significantly associated with the gene-expression profiles in both cohorts (r = 0.52 and r = 0.56, respectively). The most correlated genes were enriched in γ-aminobutyric acid (GABA) and GABA-related receptor genes (FDR q value <0.05). Moreover, the connectome gradient dysfunction at network level observed in HBV-RC patients correlated with their poor cognitive performance (Cohort 2: visual network, r = -0.56; subcortical network, r = 0.66; frontoparietal network, r = 0.51). DATA CONCLUSION: HBV-RC patients had hierarchical disorganization in the large-scale functional connectomes, which may underly their cognitive impairment. In addition, we showed the potential molecular mechanism of the connectome gradient dysfunction, which suggested the importance of GABA and GABA-related receptor genes. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Conectoma , Virus de la Hepatitis B , Humanos , Virus de la Hepatitis B/fisiología , Estudios Prospectivos , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/genética , Ácido gamma-Aminobutírico
8.
Phys Chem Chem Phys ; 25(34): 22862-22869, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37587860

RESUMEN

Natural gas hydrates have garnered significant attention as a potential new source of alternative energy, and understanding their formation mechanism is of paramount importance for efficient utilization and pipeline transportation. However, there is no consensus among academics on the formation mechanism of natural gas hydrates. In this paper, we propose a method for promoting the rapid formation of natural gas hydrates based on the rupture of methane nanobubbles, which creates local high temperature and pressure to facilitate the mixing of methane and water. The rapid decrease in system temperature and pressure during the process further enhances the formation of gas hydrates. Using molecular dynamics simulations, we theoretically verify the formation of natural gas hydrates. Our results indicate that the instantaneous rupture of methane nanobubbles induced by shock waves leads to a dramatic increase in the local molecular motion velocity around the bubbles. This results in extreme local high temperature and high pressure, leading to complete mixing of methane and water and rapid formation of gas hydrates during the cooling and pressure drop of the mixture. We confirm our findings by analyzing F3-order parameters, F4-order parameters, and water cage statistics.

9.
J Environ Manage ; 348: 119216, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37839209

RESUMEN

Invasive Spartina alterniflora has become a global management challenge in coastal wetlands. China has decided to eradicate it completely, but the high costs and its provision of beneficial ecosystem functions (EF, in the form of blue carbon and coastal protection) have raised concerns about its removal. Here, using the Yangtze Estuary as a case study, we explore a reasonable pathway of S. alterniflora management that balanced control of invasive species and EF. We simulated the spatial patterns of two key EF - blue carbon storage and wave attenuation - and identified appropriate zones for eradicating S. alterniflora based on their trade-offs. We observed contrasting patterns along the land-sea gradient for S. alterniflora community, with a decrease in blue carbon storage and an increase in wave attenuation. Notably, pioneer S. alterniflora near the foreshore displayed a high cluster of blue carbon storage (63.61 ± 7.33 Mg C ha-1) and dissipated nearly 70% of wave energy by a width of 163 m. The trade-offs between the two EF indicated that the eradication project should be implemented along the seawall rather than the foreshore. Even in the scenario of prioritized shore defense with the largest eradication zone, S. alterniflora still stored 43.1% more carbon (10.67 Gg C) compared to complete eradication and dissipated over 70% of wave energy in extreme events. Our study innovatively integrates eradication and reservation in S. alterniflora management, providing a sustainable and flexible spatial strategy that meets the needs of stakeholders.


Asunto(s)
Ecosistema , Humedales , Poaceae/metabolismo , Especies Introducidas , China , Carbono/análisis
10.
Molecules ; 28(10)2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37241875

RESUMEN

Electrocatalytic water splitting is a crucial area in sustainable energy development, and the development of highly efficient bifunctional catalysts that exhibit activity toward both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is of paramount importance. Co3O4 is a promising candidate catalyst, owing to the variable valence of Co, which can be exploited to enhance the bifunctional catalytic activity of HER and OER through rational adjustments of the electronic structure of Co atoms. In this study, we employed a plasma-etching strategy in combination with an in situ filling of heteroatoms to etch the surface of Co3O4, creating abundant oxygen vacancies, while simultaneously filling them with nitrogen and sulfur heteroatoms. The resulting N/S-VO-Co3O4 exhibited favorable bifunctional activity for alkaline electrocatalytic water splitting, with significantly enhanced HER and OER catalytic activity compared to pristine Co3O4. In an alkaline overall water-splitting simulated electrolytic cell, N/S-VO-Co3O4 || N/S-VO-Co3O4 showed excellent overall water splitting catalytic activity, comparable to noble metal benchmark catalysts Pt/C || IrO2, and demonstrated superior long-term catalytic stability. Additionally, the combination of in situ Raman spectroscopy with other ex situ characterizations provided further insight into the reasons behind the enhanced catalyst performance achieved through the in situ incorporation of N and S heteroatoms. This study presents a facile strategy for fabricating highly efficient cobalt-based spinel electrocatalysts incorporated with double heteroatoms for alkaline electrocatalytic monolithic water splitting.

11.
Molecules ; 28(6)2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36985407

RESUMEN

Cerium element with a unique electric structure can be used to modify semiconductor photocatalysts to enhance their photocatalytic performances. In this work, Ce-doped TiO2 (Ce/TiO2) was successfully achieved using the sol-gel method. The structural characterization methods confirm that Ce was doped in the lattice of anatase TiO2, which led to a smaller grain size. The performance test results show that the Ce doped in anatase TiO2 significantly enhances the charge transport efficiency and broadens the light absorption range, resulting in higher photocatalytic performance. The Ce/TiO2 exhibited a photocurrent density of 10.9 µA/cm2 at 1.0 V vs. Ag/AgCl, 2.5 times higher than that of pure TiO2 (4.3 µA/cm2) under AM 1.5 G light. The hydrogen (H2) production rate of the Ce/TiO2 was approximately 0.33 µmol/h/g, which is more than twice as much as that of the pure anatase TiO2 (0.12 µmol/h/g). This work demonstrates the effect of Ce doping in the lattice of TiO2 for enhanced photocatalytic hydrogen production.

12.
Environ Monit Assess ; 195(5): 549, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37032386

RESUMEN

Birnessite has been widely used for electrochemical removal of heavy metals due to its high pseudocapacitance. Incorporation of carbon-based materials into birnessite can enhance its conductivity and stability, and synergistically improve the electrochemical adsorption capacity due to the double-layer capacitor reaction derived from carbon-based materials. In this study, biochar was successfully incorporated with birnessite at various ratios to synthesize composites (BC-Mn) for effective electrochemical removal of cadmium (Cd(II)) from water. The effects of cell voltage, initial pH, and recycling performance of BC-Mn were evaluated. As a result, the electrosorption capacity of BC-Mn for Cd(II) exhibited gradual increases with increasing birnessite content and reached equilibrium at a Mn content of 20% (BC-Mn20). The Cd(II) adsorption capacity of BC-Mn20 rose at higher cell voltage, and reached the maximum at 1.2 V. At pH 3.0-6.0, the electrosorption capacity initially rose until pH 5.0 and then approached equilibrium with a further increase in pH value. The Cd(II) electrochemical adsorption capacity of BC-Mn20 in the solution could reach 104.5 mg g-1 at pH 5.0 for 8 h at 1.2 V. Moreover, BC-Mn20 exhibited excellent reusability with a stability of 95.4% (99.7 mg g-1) after five cycles of reuse. Due to its superior heavy metal adsorption capacity and reusability, BC-Mn20 may have a promising prospect in the remediation of heavy metal polluted water.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Cadmio/análisis , Aguas Residuales , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Metales Pesados/análisis , Carbón Orgánico/química , Agua , Adsorción
13.
Sensors (Basel) ; 22(21)2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36365945

RESUMEN

Ultra-wideband (UWB) is a promising indoor position technology with centimetre-level positioning accuracy in line-of-sight (LOS) situations. However, walls and other obstacles are common in an indoor environment, which can introduce non-line-of-sight (NLOS) and deteriorate UWB positioning accuracy to the meter level. This paper proposed a succinct method to identify NLOS induced by walls and mitigate the error for improved UWB positioning with NLOS. First, NLOS is detected by a sliding window method, which can identify approximately 90% of NLOS cases in a harsh indoor environment. Then, a delay model is designed to mitigate the error of the UWB signal propagating through a wall. Finally, all the distance measurements, including LOS and NLOS, are used to calculate the mobile UWB tag position with ordinary least squares (OLS) or weighted least squares (WLS). Experiment results show that with correct NLOS indentation and delay model, the proposed method can achieve positioning accuracy in NLOS environments close to the level of LOS. Compared with OLS, WLS can further optimise the positioning results. Correct NLOS indentation, accurate delay model and proper weights in the WLS are the keys to accurate UWB positioning in NLOS environments.

14.
J Environ Manage ; 301: 113921, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34731946

RESUMEN

Biochar has been widely applied as an adsorbent, whose electrochemical capacity and heavy metal adsorption performance can be improved by nitrogen doping. In this work, nitrogen-doped biochar (NBC) was synthesized by calcinating sodium humate with sodium bicarbonate (NaHCO3) and urea as the activation agent and nitrogen source, respectively. The NBC was then used to electrochemically adsorb Cd(II) and As(III,V) from simulated and actual wastewaters, respectively. The results indicated that NaHCO3 activation and nitrogen doping could increase the surface area and nitrogen content of the biochar, contributing to the enhancement of adsorption performance for Cd(II) and As(III,V). The electrosorption capacities for Cd(II) and total arsenic (As(T)) increased first and then reached equilibrium with increasing nitrogen content, increased first and then decreased with increasing calcination temperature, and consistently increased with increasing voltage. The Cd(II) electrosorption capacity (79.0 mg g-1) and As(T) removal ratio (94.0%) at 1.2 V in actual As-contaminated wastewater (1.16 mg L-1) were about 4 and 2.6 folds of their inorganic adsorption capacities, respectively. After five cycles of reuse, the Cd(II) and As(T) removal ratio could be maintained at 65.8% and 51.7% of the initial electrosorption capacity. This work expands the application of NBC for heavy metal removal.


Asunto(s)
Arsénico , Contaminantes Químicos del Agua , Adsorción , Cadmio , Carbón Orgánico , Nitrógeno , Aguas Residuales
15.
Molecules ; 27(24)2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36558179

RESUMEN

In this work, a simple one-step hydrothermal method was employed to prepare the Ce-doped Fe2O3 ordered nanorod arrays (CFT). The Ce doping successfully narrowed the band gap of Fe2O3, which improved the visible light absorption performance. In addition, with the help of Ce doping, the recombination of electron/hole pairs was significantly inhibited. The external voltage will make the performance of the Ce-doped sample better. Therefore, the Ce-doped Fe2O3 has reached superior photoelectrochemical (PEC) performance with a high photocurrent density of 1.47 mA/cm2 at 1.6 V vs. RHE (Reversible Hydrogen Electrode), which is 7.3 times higher than that of pristine Fe2O3 nanorod arrays (FT). The Hydrogen (H2) production from PEC water splitting of Fe2O3 was highly improved by Ce doping to achieve an evolution rate of 21 µmol/cm2/h.

16.
Angew Chem Int Ed Engl ; 61(51): e202214794, 2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36278261

RESUMEN

Designing metal-organic framework (MOF)-based catalysts with superior oxygen evolution reaction (OER) activity and robust durability simultaneously is highly required yet very challenging due to the limited intrinsic activity and their elusive evolution under harsh OER conditions. Herein, a steady self-reconstructed MOF heterojunction is constructed via redox electrochemistry and topology-guided strategy. Thanks to the inhibiting effect from hydrogen bonds of Ni-BDC-1 (BDC=1,4-benzenedicarboxylic acid), the obatained MOF heterojunction shows greatly improved OER activity with low overpotential of 225 mV at 10 mA cm-2 , relative to the totally reconstructed Ni-BDC-3 (332 mV). Density function theory calculations reveal that the formed built-in electric field in the MOF heterojunction remarkably optimizes the ad/desorption free energy of active Ni sites. Moreover, such MOF heterojunction shows superior durability attributed to the shielding effect of the surface-evolved NiOOH coating.

17.
Small ; 17(39): e2102699, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34396696

RESUMEN

g-C3 N4 /CdS heterojunctions are potential photocatalysts for hydrogen production but their traditional type-II configuration generally leads to weak oxidative and reductive activity. How to construct the novel Z-scheme g-C3 N4 /CdS counterparts to address this issue remains a great challenge in this field. In this work, a new direct Z-scheme heterojunction of defective g-C3 N4 /CdS is designed by introducing cyano groups (NC-) as the active bridge sites. Experimental observations in combination with density functional theory (DFT) calculations reveal that the unique electron-withdrawing feature of cyano groups in the defective g-C3 N4 /CdS heterostructure can endow this photocatalyst with numerous advantageous properties including high light absorption ability, strong redox performance, satisfactory charge separation efficiency, and long lifetime of charge carriers. Consequently, the resultant photocatalytic system exhibits more active performance than CdS and g-C3 N4 under visible light and reaches an excellent hydrogen evolution rate of 1809.07 µmol h-1 g-1 , which is 6.09 times higher than pristine g-C3 N4 . Moreover, the defective g-C3 N4 /CdS photocatalyst maintains good stability after 40 h continuous test. This work provides new insights into design and construction of Z-scheme heterojunctions for regulating the visible-light-induced photocatalytic activity for H2 evolution.

18.
J Magn Reson Imaging ; 54(6): 1830-1840, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34031950

RESUMEN

BACKGROUND: The diseased-related dynamic functional network connectivity (dFNC) disruption and its relationship with cognitive impairment in hepatitis B virus-related cirrhosis (HBV-RC) patients with minimal hepatic encephalopathy (MHE) and no MHE (NMHE) remain unknown. This knowledge would help identify MHE pathophysiology and monitor disease progression in HBV-RC patients. PURPOSE: To investigate the dFNC in patients with NMHE and MHE and the relationship between dFNC indices with the psychometric hepatic encephalopathy score (PHES). STUDY TYPE: Prospective. POPULATION: Thirty HBV-RC patients (including 17 NMHE and 13 MHE) and 38 healthy controls (HC). FIELD STRENGTH/SEQUENCE: A 1.5 T MRI and gradient-echo echo-planar imaging and fast field echo three-dimensional T1-weighted imaging. ASSESSMENT: The independent components, dFNC matrix and dFNC indices (mean dwell times [DT], number of states, number of transitions, and fraction time in each state), were obtained through GIFT package. Cognitive measurement and patients grouping were based on PHES tests. STATISTICAL TESTS: One-way ANOVA, chi-square test, two-sample t-test, Kruskal-Wallis test, spearman's correlation analysis and the false discovery rate. Significance level: P < 0.05. RESULTS: Compared to HC (21.1 ± 4.02), the DT of state 1 decreased in NMHE (9.0 ± 3.04, P = 0.062, 95% confidence interval [CI] is -0.65 to 24.88) and significantly in MHE stage (1.2 ± 1.01) and was significantly correlated with PHES (r = 0.5) for all patients. The DT of state 2 increased gradually in NMHE (75.2 ± 13.10, P = 0.052, 95% CI, -54.23 to 0.28) and significantly in MHE stage (94.6 ± 15.61) when compared to HC (48.2 ± 6.97). Moreover, the connectivity between cognitive control network (CCN) and visual network (VIS) in state 1 (0.7 ± 0.79) and between default mode (DMN) and VIS in state 2 (-0.2 ± 0.29) decreased significantly in MHE when compared to HC (0.1 ± 0.68 for CCN-VIS in state 1 and 0.1 ± 0.17 for DMN-VIS for state 2). DATA CONCLUSION: dFNC exhibited progressive impairment as the disease advances in patients with HBV-RC. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Encefalopatía Hepática , Virus de la Hepatitis B , Encéfalo/patología , Encefalopatía Hepática/diagnóstico por imagen , Encefalopatía Hepática/patología , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/patología , Imagen por Resonancia Magnética , Estudios Prospectivos
19.
Sensors (Basel) ; 21(24)2021 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-34960360

RESUMEN

CeO2/ZnO-heterojunction-nanorod-array-based chemiresistive sensors were studied for their low-operating-temperature and gas-detecting characteristics. Arrays of CeO2/ZnO heterojunction nanorods were synthesized using anodic electrodeposition coating followed by hydrothermal treatment. The sensor based on this CeO2/ZnO heterojunction demonstrated a much higher sensitivity to NO2 at a low operating temperature (120 °C) than the pure-ZnO-based sensor. Moreover, even at room temperature (RT, 25 °C) the CeO2/ZnO-heterojunction-based sensor responds linearly and rapidly to NO2. This sensor's reaction to interfering gases was substantially less than that of NO2, suggesting exceptional selectivity. Experimental results revealed that the enhanced gas-sensing performance at the low operating temperature of the CeO2/ZnO heterojunction due to the built-in field formed after the construction of heterojunctions provides additional carriers for ZnO. Thanks to more carriers in the ZnO conduction band, more oxygen and target gases can be adsorbed. This explains the enhanced gas sensitivity of the CeO2/ZnO heterojunction at low operating temperatures.

20.
New Phytol ; 227(2): 407-426, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32145071

RESUMEN

Root growth control plays an important role in plant adaptation to drought stress, but the underlying molecular mechanisms of this control remain largely elusive. Here, a root-specific nuclear factor Y (NF-Y) transcription factor PdNF-YB21 was isolated from Populus. The functional mechanism of PdNF-YB21 was characterised by various morphological, physiological, molecular, biochemical and spectroscopy techniques. Overexpression of PdNF-YB21 in poplar promoted root growth with highly lignified and enlarged xylem vessels, resulting in increased drought resistance. By contrast, CRISPR/Cas9-mediated poplar mutant nf-yb21 exhibited reduced root growth and drought resistance. PdNF-YB21 interacted with PdFUSCA3 (PdFUS3), a B3 domain transcription factor. PdFUS3 directly activated the promoter of the abscisic acid (ABA) synthesis key gene PdNCED3, resulting in a significant increase in root ABA content in poplars subjected to water deficit. Coexpression of poplar NF-YB21 and FUS3 significantly enhanced the expression of PdNCED3. Furthermore, ABA promoted indoylacetic acid transport in root tips, which ultimately increased root growth and drought resistance. Taken together, our data indicate that NF-YB21-FUS3-NCED3 functions as an important avenue in auxin-regulated poplar root growth in response to drought.


Asunto(s)
Populus , Ácido Abscísico , Factor de Unión a CCAAT , Sequías , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Populus/genética , Populus/metabolismo , Factores de Transcripción/genética
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