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1.
Nat Commun ; 15(1): 8269, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39333086

RESUMO

Per- and poly-fluoroalkyl substances (PFAS) have gained widespread attention due to their adverse effects on health and environment. Developing efficient technology to capture PFAS from contaminated sources remains a great challenge. In this study, we introduce a type of reusable polymeric sorbent (PFPE-IEX + ) for rapid, efficient, and selective removal of multiple PFAS impurities from various contaminated water sources. The resin achieves >98% removal efficiency ([PFPE-IEX + ] = 0.5-5 mg mL-1, [PFAS]0 = 1-10 ppb in potable water and landfill leachate) and >500 mg g-1 sorption capacity for the 11 types of examined PFAS. We achieve efficient PFAS removal without breakthrough and subsequent resin regeneration and demonstrate good PFAS recovery in a proof-of-concept cartridge setup. The outcomes of this study offer valuable guidance to the design of platforms for efficient and selective PFAS capture from contaminated water, such as drinking water and landfill leachate.

2.
J Colloid Interface Sci ; 638: 220-230, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36738545

RESUMO

This work reports the incorporation of coordinated water into Ni-BTC nanorods (Ni-BTC-O) which induces their structural transformation to Ni-BTC nanofibres (Ni-BTC-F). The carbonization of the Ni-BTC nanofibres at 600 °C results in the formation of carbon nanotube (CNT)-decorated hierarchical porous nickel/carbon hybrid (labelled as Ni/C-600) with enlarged pores. In contrast, the Ni/C hybrid obtained from the carbonization of the original (unmodified) Ni-BTC nanorods (Ni-BTC-O) at 600 °C (labelled as Ni-BTC-O-600) exhibits smaller pore size and does not show the formation of CNTs. The Ni/C-600 hybrid derived from Ni-BTC-F shows a very high adsorption capacity of 686.8 mg g-1 toward methyl blue (MB) dye. This is approximately 4.8 times higher than the adsorption capacity of Ni-BTC-O-600 (144.1 mg g-1). The higher adsorption performance of Ni/C-600 relative to Ni-BTC-O-600 can be attributed to its larger pore volume, hierarchical porosity, and additional adsorption sites provided by the CNTs. In addition, the Ni/C-600 hybrid can maintain 90% of its adsorption capacity after 5 consecutive cycles, demonstrating its potential as an efficient and recyclable adsorbent for MB dye.


Assuntos
Estruturas Metalorgânicas , Nanotubos de Carbono , Estruturas Metalorgânicas/química , Níquel/química , Porosidade , Adsorção
3.
Quant Imaging Med Surg ; 12(5): 2891-2903, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35502372

RESUMO

Background: To determine the predictive value of carotid plaque characteristics for the improvement of cognition in patients with moderate-to-severe carotid stenosis after carotid endarterectomy (CEA), using vessel wall magnetic resonance imaging (MRI). Methods: This was a prospective cohort study. Patients with unilateral, moderate-to-severe carotid stenosis referred to the Peking University Third Hospital for CEA were prospectively recruited and underwent carotid vessel wall MRI within 1 week before CEA. We performed Montreal Cognitive Assessment (MoCA) within 1 week before and 3-4 days after CEA. The morphological and compositional characteristics of carotid plaques on MRI were evaluated. Improvement of cognition was defined as >10% increase of the total MoCA score after CEA compared with baseline. Carotid plaque characteristics were compared between patients with and without cognitive improvement. Results: In total, 105 patients (91 males; mean age, 65.5±8.4 years) were included. The volume {48.0 [interquartile range (IQR), 21.0 to 91.6] vs. 16.3 (IQR, 8.1 to 53.1) mm3; P=0.005} and cumulative slice [4.0 (IQR, 3.0 to 7.0) vs. 3.0 (IQR, 2.0 to 5.0); P=0.019] of carotid calcification, and maximum percentage of calcification area [13.1% (IQR, 6.0% to 19.8%) vs. 6.2% (IQR, 3.7% to 10.8%); P=0.004] were significantly smaller in participants with cognitive improvement compared to those without. Univariate logistic regression analysis showed that volume [odds ratio (OR) =0.994; 95% confidence interval (CI): 0.989 to 1.000; P=0.043] and cumulative slice (OR =0.823; 95% CI: 0.698 to 0.970; P=0.020) of carotid calcification, and maximum percentage of calcification area (OR =0.949; 95% CI: 0.909 to 0.991; P=0.018) were significantly correlated with cognitive improvement. After adjusting for confounding factors, these associations remained statistically or marginally significant (volume: OR =0.994; 95% CI: 0.988 to 1.000; P=0.057; maximum percentage of calcification area: OR =0.937; 95% CI: 0.890 to 0.987; P=0.014; and cumulative slice: OR =0.791; 95% CI: 0.646 to 0.967; P=0.022). No significant associations were found between other plaque characteristics and cognitive improvement (all P>0.05). Conclusions: More than half of the participants with unilateral, moderate-to-severe carotid atherosclerotic stenosis had cognitive improvement. The size of calcification might be an effective indicator of cognitive improvement after CEA.

4.
Nat Protoc ; 17(12): 2990-3027, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36064756

RESUMO

Metal-organic frameworks (MOFs), or porous coordination polymers, are crystalline porous materials formed by coordination bonding between inorganic and organic species on the basis of the self-assembly of the reacting units. The typical characteristics of MOFs, including their large specific surface areas, ultrahigh porosities and excellent thermal and chemical stabilities, as well as their great potential for chemical and structural modifications, make them excellent candidates for versatile applications. Their poor electrical conductivity, however, has meant that they have not been useful for electrochemical applications. Fortuitously, the direct carbonization of MOFs results in a rearrangement of the carbon atoms of the organic units into a network of carbon atoms, which means that the products have useful levels of conductivity. The direct carbonization of zeolitic imidazolate framework (ZIF)-type MOFs, particularly ZIF-8, has successfully widened the scope of possible applications of MOFs to include electrochemical reactions that could be used in, for example, energy storage, energy conversion, electrochemical biosensors and capacitive deionization of saline water. Here, we present the first detailed protocols for synthesizing high-quality ZIF-8 and its modified forms of hollow ZIF-8, core-shell ZIF-8@ZIF-67 and ZIF-8@mesostuctured polydopamine. Typically, ZIF-8 synthesis takes 27 h to complete, and subsequent nanoarchitecturing procedures leading to hollow ZIF-8, ZIF-8@ZIF-67 and ZIF-8@mPDA take 6, 14 and 30 h, respectively. The direct-carbonization procedure takes 12 h. The resulting nanoporous carbons are suitable for electrochemical applications, in particular as materials for supercapacitors.


Assuntos
Estruturas Metalorgânicas , Nanoporos , Zeolitas , Carbono , Porosidade
5.
Angiology ; 73(2): 104-111, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34018407

RESUMO

We compared plaque characteristics between symptomatic and asymptomatic sides in patients with bilateral carotid vulnerable plaques using magnetic resonance imaging (MRI). Participants (n = 67; mean age: 65.8 ± 7.7 years, 61 males) with bilateral carotid vulnerable plaques were included. Vulnerable plaques were characterized by intraplaque hemorrhage (IPH), large lipid-rich necrotic core (LRNC), or fibrous cap rupture (FCR) on MRI. Symptomatic vulnerable plaques showed greater plaque burden, LRNC volume (median: 221.4 vs 134.8 mm3, P = .003), IPH volume (median: 32.2 vs 22.5 mm3, P = .030), maximum percentage (Max%) LRNC (median: 51.3% vs 41.8%, P = .002), Max%IPH (median: 13.4% vs 9.5%, P = .022), cumulative slices of LRNC (median: 10 vs 8, P = .005), and more juxtaluminal IPH and/or thrombus (29.9% vs 6.0%, P = .001) and FCR (37.3% vs 16.4%, P = .007) than asymptomatic ones. After adjusting for plaque burden, differences in juxtaluminal IPH and/or thrombus (odds ratio [OR]: 5.49, 95% CI: 1.61-18.75, P = .007) and FCR (OR: 2.90, 95% CI: 1.16-7.24, P = .022) between bilateral sides remained statistically significant. For patients with bilateral carotid vulnerable plaques, symptomatic plaques had greater burden, more juxtaluminal IPH and/or thrombus, and FCR compared with asymptomatic ones. The differences in juxtaluminal IPH and/or thrombus and FCR between bilateral sides were independent of plaque burden.


Assuntos
Aterosclerose , Estenose das Carótidas , Placa Aterosclerótica , Idoso , Artérias Carótidas/diagnóstico por imagem , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
6.
ACS Appl Mater Interfaces ; 13(44): 52034-52043, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34459576

RESUMO

Herein, the synergistic effects of hollow nanoarchitecture and high specific surface area of hollow activated carbons (HACs) are reported with the superior supercapacitor (SC) and capacitive deionization (CDI) performance. The center of zeolite imidazolate framework-8 (ZIF-8) is selectively etched to create a hollow cavity as a macropore, and the resulting hollow ZIF-8 (HZIF-8) is carbonized to obtain hollow carbon (HC). The distribution of nanopores is, subsequently, optimized by KOH activation to create more nanopores and significantly increase specific surface area. Indeed, as-prepared hollow activated carbons (HACs) show significant improvement not only in the maximum specific capacitance and desalination capacity but also capacitance retention and mean desalination rates in SC and CDI, respectively. As a result, it is confirmed that well-designed nanoarchitecture and porosity are required to allow efficient diffusion and maximum electrosorption of electrolyte ions.

7.
J Geriatr Cardiol ; 17(4): 202-209, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32362918

RESUMO

OBJECTIVE: To determine the association of carotid plaque features with collateral circulation status in elderly patients with moderate to severe carotid stenosis. METHODS: Elderly patients (> 60 years) with moderate to severe carotid stenosis were recruited and categorized into good and poor collateral circulation groups, and underwent magnetic resonance imaging and computed tomography imaging. The carotid plaque features including lipid-rich necrotic core, intraplaque hemorrhage, calcification, and fibrous cap rupture (FCR) were evaluated, and maximum wall thickness, normalized wall index (NWI), and luminal stenosis were measured. The association between these variables and collateral circulation status was analyzed. RESULTS: Of the 97 patients (78 males, mean age: 69.0 ± 6.1 years), 19 (19.6%) had poor collaterals. The poor collateral group had a significantly higher NWI (93.7% ± 5.0% vs. 89.0% ± 7.9%, P = 0.011), a greater extent of stenosis (80.0% ± 11.4% vs. 75.3% ± 9.4%, P = 0.036) and FCR (84.2% vs. 55.1%, P = 0.020) compared with good collateral group. Carotid NWI (OR = 3.83, 95% CI: 1.36-10.82, P = 0.011) and more FCR (OR = 6.77, 95% CI: 1.35-33.85, P = 0.020) were associated with poor collateral circulation after adjustment for the confounding factors. The combination of NWI, FCR, systolic blood pressure, and triglycerides had the highest area-under-the-curve (AUC = 0.85) for detection of poor collaterals. CONCLUSIONS: Carotid plaque features, specifically NWI and FCR, are independently associated with poor collateral circulation, and the combination of carotid plaque features and traditional risk factors has a stronger predictive value for poor collateral circulation than plaque features alone.

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