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1.
Bull Environ Contam Toxicol ; 110(1): 37, 2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36607448

RESUMEN

Phytoextraction is an efficient strategy for remediating heavy metal-contaminated soil. Chelators can improve the bioavailability of heavy metals and increase phytoextraction efficiency. However, traditional chelators have gradually been replaced due to secondary pollution. In this study, a typical organic acid (citric acid, CA) and a novel biodegradable chelator (poly-glutamic acid, PGA), were investigated using pot experiments to compare the phytoextraction efficiency of Solanum nigrum L. (a Cd (hyper)accumulator) for cadmium (Cd) and lead (Pb) in contaminated soil. The results showed CA and PGA significantly improved plant growth, and total Cd and Pb amounts of S. nigrum, both CA and PGA significantly increased the shoot Cd and Pb concentrations. However, only PGA significantly increased the root Pb concentration. CA and PGA application promoted the bioavailability of Cd and Pb in rhizosphere soils and their translocations from roots to shoots in S. nigrum. Both CA and PGA increased the phytoextraction efficiency of Cd and Pb in S. nigrum plants, and the PGA for Cd and Pb phytoextraction was more effective than CA. Our findings demonstrate that the biodegradable chelator PGA has great potential for enhancing phytoextraction from compound Cd-Pb contaminated soils, suggesting that biodegradable chelator-assisted phytoextraction with (hyper)accumulator is strongly recommended in severely contaminated sites.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Solanum nigrum , Cadmio/análisis , Ácido Glutámico , Plomo , Ácido Cítrico , Biodegradación Ambiental , Contaminantes del Suelo/análisis , Metales Pesados/análisis , Quelantes/farmacología , Suelo
2.
Phys Chem Chem Phys ; 23(45): 25789-25796, 2021 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-34766607

RESUMEN

Organic molecules with thermally activated delayed fluorescence (TADF) and aggregation induced emission (AIE) properties have attracted increasing research interest due to their great potential applications in organic light emitting diodes (OLEDs), especially for those with multicolor mechanochromic luminescence (MCL) features. Theoretical research on the luminescence characteristics of organic TADF emitters based on the aggregation states is highly desired to quantify the relationship between the TADF properties and aggregation states. In this work, we study the 4,4'-(6-(9,9-dimethylacridine-10(9H)-yl)quinoline-2,3-dibenzonitrile (DMAC-CNQ) emitter with TADF and AIE properties, and calculate the photophysical properties in gas, solid and amorphous states by using the quantum mechanics and molecular mechanics (QM/MM) method. Our simulations demonstrate that the aggregation states enhance obviously the reverse intersystem crossing rates and transition dipole moments of the DMAC-CNQ emitter, and suppress the non-radiative rates from the lowest excited singlet state (S1) to ground state (S0). Specifically, the molecular stacking of DMAC-CNQ in solid phases can mainly restrict the geometric torsion of the DMAC moiety for decreasing non-radiative decay rates, and the torsion of the CNQ moiety for increasing the reverse intersystem crossing rates. As a result, the calculated fluorescence efficiencies of the DMAC-CNQ emitter in the crystal and amorphous states are 67% and 26% respectively, and in good agreement with the experimental results.

3.
Clin Neuroradiol ; 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38451269

RESUMEN

OBJECTIVE: To investigate the safety and efficacy of LVIS Jr stent-assisted coiling (SAC) of intracranial aneurysms (IAs) in small-diameter parent arteries and determine the factors influencing incomplete aneurysm occlusion. MATERIAL AND METHODS: Clinical and imaging data of 130 patients with IAs in small-diameter parent arteries that were treated with LVIS Jr SAC were retrospectively analyzed. Stent apposition was evaluated by high-resolution flat detector CT, and aneurysm embolization density was evaluated using 2D-DSA. Perioperative complications were recorded. Multivariate logistic regression analyses were performed to determine possible factors for incomplete aneurysm occlusion. RESULTS: In this study, 130 patients (60 and 70 patients with ruptured and unruptured aneurysms, respectively) were successfully treated with LVIS Jr SAC. Immediate digital subtraction angiography (DSA) showed that the aneurysm occlusion was Raymond-Roy class I, II, IIIa, and IIIb in 93 (71.5%), 24 (18.5%), 8 (6.2%), and 5 (3.8%) cases, respectively. There were three cases of acute in-stent thrombosis and two cases of severe vasospasm observed during the perioperative period. The 6­month follow-up angiograms indicated that complete aneurysm occlusion in 122 patients was 79.5% (97/122). Multivariate logistic regression analyses showed that an aneurysm size > 10.0 mm, parent artery mean diameter < 2.0 mm, and incomplete stent apposition at the aneurysm neck were possible risk factors for incomplete aneurysm occlusion. CONCLUSION: The LVIS Jr SAC is effective for managing IAs in small-diameter parent arteries. An aneurysm size > 10.0 mm, parent artery mean diameter < 2.0 mm, and incomplete stent apposition at the aneurysm neck are possible risk factors for incomplete aneurysm occlusion.

4.
Environ Sci Pollut Res Int ; 31(5): 7533-7542, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38159183

RESUMEN

Biochar, as a soil amendment, can be applied to remediate heavy metal (HM) contaminated farmland. However, there is little research on the effect of tobacco biochar (TB) derived from tobacco waste on HM controlling in edible parts of vegetables. In this study, the impact of two TB levels on the plant growth, copper (Cu) and cadmium (Cd) accumulation in the edible parts of lettuce and chrysanthemum, and on Cu and Cd bioavailability of rhizosphere soil was investigated through in-situ field experiments. The results showed that TB has rich oxygen containing functional groups, high porosity, high nitrogen adsorption capacity. The addition of 5 t ha-1 and 10 t ha-1 TB significantly increased the shoot biomass of chrysanthemum, but had no effect on the growth of lettuce. Two levels of TB significantly increased the pH value, but decreased the available Cu and Cd concentrations of rhizosphere soil, thereby reducing the Cu and Cd accumulations in the edible parts of lettuce and chrysanthemum. The findings provided effective evidences that TB derived from tobacco waste is an efficient strategy for controlling Cu and Cd accumulation in the edible parts of vegetables to ensure agri-product safety production in HM-polluted farmland.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Cadmio/análisis , Cobre , Verduras , Contaminantes del Suelo/análisis , Metales Pesados/análisis , Carbón Orgánico , Nicotiana , Suelo , Lactuca
5.
Interv Neuroradiol ; : 15910199241254864, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38751187

RESUMEN

PURPOSE: This study aims to compare the efficacy and safety of using overlapping low-profile visualized intraluminal support (LVIS) devices and flow diversion (FD) for the treatment of unruptured vertebral artery dissection (VAD) in the V3-V4 segments. METHODS: The clinical and imaging data of 71 patients with unruptured VAD in the V3-V4 segments who underwent either dual LVIS stenting (d-LVIS group) or single FD stenting (FD group) at our center from September 2014 to December 2021 were retrospectively analyzed. RESULTS: Immediate postoperative angiography revealed no significant difference in the degree of occlusion between the two groups in treating vertebral artery dissecting aneurysms (with or without noncompact coiling). However, the d-LVIS group had significantly higher fluoroscopy exposure time and total radiation exposure dose compared to the FD group. During the perioperative period, two cases of pontine infarction and one case of acute thrombosis were encountered. One patient died from subarachnoid hemorrhage during the follow-up period. For dissecting the aneurysm, angiographic follow-up (8.56 ± 1.96 months) showed similar healing outcomes between the two groups (with or without noncompact coiling). However, seven patients (7/40, 17.5%) showed poor healing and one patient showed mild in-stent stenosis. For simple dissection, angiographic follow-up (8.78 ± 1.83 months) showed patent lumens in both groups, with all dissections healing well, and two patients having mild in-stent stenosis. CONCLUSION: Both methods could effectively treat unruptured VAD in V3-V4 segments. Nevertheless, simple FD implantation is relatively easier to perform and involves lower radiation exposure.

6.
AJNR Am J Neuroradiol ; 45(7): 899-905, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38871372

RESUMEN

BACKGROUND AND PURPOSE: The Neuroform Atlas stent and the LVIS Jr stent are intracranial microstent systems for the treatment of wide-neck intracranial aneurysms. Hence, this study aimed to compare the efficacy and safety of the Neuroform Atlas stent and the LVIS Jr stent for the treatment of unruptured intracranial aneurysms in parent arteries of <2 mm in diameter. MATERIALS AND METHODS: From March 2022 to April 2023, the clinical and imaging data of 135 patients with unruptured intracranial aneurysms treated with stent-assisted coiling using the Neuroform Atlas or LVIS Jr stent in parent arteries of <2 mm in diameter were retrospectively analyzed. Stent apposition was evaluated by high-resolution conebeam CT (HR-CBCT). Immediate aneurysm-embolization attenuation and occlusion at 6-month follow-up were evaluated using 2D DSA and the modified Raymond-Roy classification. Adverse events were recorded. Multivariate logistic regression analysis was undertaken to determine the independent factors affecting incomplete stent apposition. RESULTS: One hundred thirty-five patients (135 aneurysms) underwent stent-assisted coiling (66 Neuroform Atlas stents and 69 LVIS Jr stents). Intraoperative HR-CBCT showed that 1 Neuroform Atlas stent and 11 LVIS Jr stents had incomplete stent apposition at the aneurysm neck (P < .05). Perioperative complications occurred in 3 cases (2.22%). These comprised 2 cases of neurologic complications (1 case of distal intracranial vascular embolism and 1 case of cerebral parenchymal hemorrhage) and 1 case of severe postprocedural gastrointestinal hemorrhage. DSA follow-up showed 3 cases of aneurysm recurrence in the LVIS Jr group. Multivariate regression analysis showed that a stent angle of ≥75° (OR, 23.963; P = .005) or a parent artery diameter mismatch ratio of ≥1.25 (OR, 8.043; P = .037) were risk factors for incomplete stent apposition, especially for the LVIS Jr stent (OR, 20.297; P = .015). CONCLUSIONS: The Neuroform Atlas stent and LVIS Jr stent are efficacious in the treatment of unruptured intracranial aneurysms in parent arteries of <2 mm in diameter. Apposition of the LVIS Jr stent was worse than in the Neuroform Atlas stent at the neck of some aneurysms.


Asunto(s)
Embolización Terapéutica , Aneurisma Intracraneal , Stents , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/terapia , Aneurisma Intracraneal/cirugía , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Embolización Terapéutica/instrumentación , Embolización Terapéutica/métodos , Adulto , Resultado del Tratamiento , Procedimientos Endovasculares/instrumentación , Procedimientos Endovasculares/métodos , Angiografía Cerebral , Tomografía Computarizada de Haz Cónico , Angiografía de Substracción Digital
7.
Environ Sci Pollut Res Int ; 30(10): 25755-25763, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36348238

RESUMEN

Arbuscular mycorrhizal (AM) fungi are known to have beneficial effects on host plants growing on contaminated soils. The present study aimed at investigating the influence of two different AM fungi (Rhizophagus intraradices and Funneliformis mosseae) on the growth of plants and Cu uptake by Mimosa pudica L. grown in polluted soils containing various levels of Cu (Control, 400, 500, or 600 mg kg-l soil) in pot experiments. Mycorrhizal colonisation rates by the two AM fungi decreased markedly with the increasing Cu levels in soils. This inhibition was more pronounced to F. mosseae than R. intraradices, indicating that R. intraradices was more tolerant to Cu than F. mosseae. Compared with non-mycorrhizal plants, R. intraradices inoculation increased plant growth (including shoot height, numbers of compound leaves and leaflets, and dry biomass) and P concentrations in the shoots and roots of M. pudica at all levels of Cu. Meanwhile, F. mosseae displayed a capability of growth promotion to M. pudica much later and lower than R. intraradices. F. mosseae and R. intraradices markedly decreased Cu concentration in shoots at 400-600 mg kg-1 Cu levels. However, R. intraradices was more efficient than F. mosseae in decreasing the shoot Cu concentrations. As for the increasing Cu tolerance by R. intraradices, possibly it was reached though the improvement of phosphorus nutrition and the decline of Cu transport from roots to shoots of M. pudica. R. intraradices showed a good potential for improving medicinal plants growth and declining toxic effects in Cu-contaminated soils.


Asunto(s)
Mimosa , Micorrizas , Contaminantes del Suelo , Micorrizas/fisiología , Raíces de Plantas/microbiología , Contaminación Ambiental , Suelo
8.
AJNR Am J Neuroradiol ; 45(1): 16-21, 2023 12 29.
Artículo en Inglés | MEDLINE | ID: mdl-38164561

RESUMEN

BACKGROUND AND PURPOSE: Flow diversion treatment repairs aneurysms by altering the hemodynamics of the aneurysmal sac and providing a scaffold for endothelial cell adhesion. The purpose of this study was to investigate the correlation of flow diverter (FD) malapposition at the aneurysm neck with incomplete occlusion of small intracranial aneurysms (IAs) and investigate other factors that are possibly related to incomplete occlusion. MATERIALS AND METHODS: From January 2019 to June 2022, the clinical and imaging data for 153 patients (175 aneurysms) with unruptured small IAs treated with flow diversion were retrospectively analyzed. FD apposition at the aneurysm neck was evaluated by high-resolution conebeam CT (HR-CBCT), and the complete occlusion rate for aneurysms was judged according to the latest follow-up conventional angiography findings (≥6 months). Multivariate logistic regression analysis was used to determine factors associated with incomplete aneurysm occlusion. RESULTS: In total, 159 FDs were implanted in 153 patients. HR-CBCT performed after the deployment revealed FD malapposition at the aneurysm neck in 18 cases. According to the latest follow-up angiograms (average: 9.47 ± 3.35 months), the complete aneurysm occlusion rate was 66.9%. The complete occlusion rates for incomplete and complete stent apposition at the neck were 38.9% (7/18) and 70.1% (110/157), respectively. The results of regression analysis showed that an aneurysm sac with branch vessels (OR, 2.937; P = .018), incomplete stent apposition at the aneurysm neck (OR, 3.561; P = .023), and a large aneurysm diameter (OR, 1.533; P = .028) were positive predictors of incomplete aneurysm occlusion. CONCLUSIONS: An aneurysm sac with branch vessels, a large aneurysm diameter, and malapposition at the aneurysm neck significantly affect aneurysm repair after FD stent-only treatment for small IAs.


Asunto(s)
Embolización Terapéutica , Procedimientos Endovasculares , Aneurisma Intracraneal , Humanos , Aneurisma Intracraneal/terapia , Resultado del Tratamiento , Estudios Retrospectivos , Stents , Angiografía , Embolización Terapéutica/métodos , Procedimientos Endovasculares/métodos
9.
Dalton Trans ; 51(2): 463-467, 2022 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-34929728

RESUMEN

Introduction of the planar organic cation [C(NH2)3]+ into tetrahedronal inorganic arsenate generates a new ultraviolet nonlinear optical crystal triguanidine arsenate dihydrate, [C(NH2)3]3AsO4·2H2O, which exhibits a short ultraviolet absorption edge (210 nm), suitable second-harmonic generation response (0.9 × KDP), and moderate birefringene (0.0387 at 546 nm). Notably, by optimizing the growth conditions, transparent and wafer well-developed bulk single crystals can be easily prepared.

10.
ACS Appl Mater Interfaces ; 13(39): 46909-46918, 2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34550667

RESUMEN

Small-molecule thermally activated delayed fluorescence (TADF) materials have been extensively developed to actualize efficient organic LEDs (OLEDs). However, organic small molecules generally compromise thin film quality and stability due to the tendency of crystallization, aggregation, and phase separation, which hence degrade the efficiency and long-term stability of the OLEDs. Here, for the first time, we exploit the unique molecular configuration of the bimesitylene scaffold to design two highly efficient TADF amorphous molecular materials with excellent thermal and morphological stabilities. The twisted and rigid bimesitylene scaffold thwarts regular molecular packing and crystallization, thereby guaranteeing homogeneous and stable amorphous thin films. Meanwhile, the highly twisted geometry of the bimesitylene scaffold efficiently breaks the molecular conjugation and thus conserves the high energies of the lowest locally excited triplet states (3LE) above the lowest charge transfer states (1CT and 3CT), leading to small singlet-triplet energy splitting and fast reverse intersystem crossing. These TADF emitters exhibit high photoluminescence quantum yields of 0.90 and 0.69 and short TADF lifetimes of 4.94 and 1.44 µs in doped films, based on which the greenish-blue and greenish-yellow OLEDs achieve external quantum efficiencies of 23.2 and 16.2%, respectively, with small efficiency roll-off rates and perfect color stability.

11.
Small Methods ; 5(9): e2100649, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34928050

RESUMEN

Emerging catalytic host for sulfur is an effective approach to breaking the limits of lithium-sulfur batteries for practical applications. Herein, the hydrangea-shaped Co0.85 Se electrocatalyst with macroporous architecture is synthesized. Besides, to improve the electronic conductivity of Co0.85 Se, some defects (S-doped) are introduced into the structure of crystals. The S-doped Co0.85 Se exhibited an outstanding electrocatalytic effect on lithium polysulfides conversion and can induce and regulate uniform growth of insoluble Li2 S on its surface due to the synergistic adsorption by Se and S. As a result, the S/C cathode achieved a high initial capacity of 1340.6 mAh g-1 at 0.5 C and a stable cycling capacity of 666.6 mAh g-1 at 1 C after 500 cycles by 5 wt% Co0.85 SeS additions. Moreover, high S loading cathodes are designed through in situ synthesis of Co0.85 SeS on flexible carbon cloth (Co0.85 SeS@CC). The porous and open framework of Co0.85 SeS@CC facilitated electrolyte infiltration and accommodated the volume change of sulfur during the charge/discharge process. Taking by these advantages, a high areal capacity of 9.663 mAh cm-2 is achieved at a high sulfur loading of 9.98 mg cm-2 . Even at a high current density of 15 mA cm-2 , a reversible capacity of 603.7 mAh g-1 is maintained at a sulfur loading of 6.52 mg cm-2 . This proposed work provides a feasible approach to high-rate and flexible Li-S batteries.

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