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1.
ACS Biomater Sci Eng ; 10(1): 191-218, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38052003

RESUMO

As noninvasive wearable electronic devices, epidermal sensors enable continuous, real-time, and remote monitoring of various human physiological parameters. Conductive biomaterials-based hydrogels as sensor matrix materials have good biocompatibility, biodegradability, and efficient stimulus response capabilities and are widely applied in motion monitoring, healthcare, and human-machine interaction. However, biomass hydrogel-based epidermal sensing devices still need excellent mechanical properties, prolonged stability, multifunctionality, and extensive practicality. Therefore, this paper reviews the common biomass hydrogel materials for epidermal sensing (proteins, polysaccharides, polyphenols, etc.) and the various types of noninvasive sensing devices (strain/pressure sensors, temperature sensors, glucose sensors, electrocardiograms, etc.). Moreover, this review focuses on the strategies of scholars to enhance sensor properties, such as strength, conductivity, stability, adhesion, and self-healing ability. This work will guide the preparation and optimization of high-performance biomaterials-based hydrogel epidermal sensors.


Assuntos
Materiais Biocompatíveis , Hidrogéis , Humanos , Polifenóis
2.
Eur Radiol ; 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38006453

RESUMO

OBJECTIVES: We proposed a strategy for the creation of a 6-mm transjugular intrahepatic portosystemic shunt (TIPS) and to assess its effectiveness compared to a conventional 8-mm shunt for TIPS-induced hepatic encephalopathy (HE). METHODS: Patients were reviewed retrospectively using propensity score matching (1:1) and divided into 6-mm and 8-mm shunt groups based on shunt diameter. The stent patency, HE incidence, and rebleeding rate between the two groups were then compared. RESULTS: From January 2018 to June 2021, both 6-mm shunt group and 8-mm shunt group included 58 patients. The 6-mm shunt group had significantly smaller liver volumes (879.3 ± 237.1 vs. 1008.8 ± 293.0; p = 0.010), and the median stent patency times were 30.7 and 33.8 months in the 6-mm and 8-mm groups, respectively (p = 0.124). No statistically significant difference was found between the two groups in the 1-year (8.6% vs. 3.4%; p = 0.242) and 2-year (17.2% vs. 12.1%; p = 0.242) rebleeding rates. The 1-year cumulative incidences of overt HE were 12.1% and 27.6% in the 6-mm and 8-mm groups, respectively (p = 0.040), and the 2-year cumulative overt HE incidences in these groups were 19.0% and 36.2%, respectively (p = 0.038). Notably, patients with a 6-mm shunt also experienced less hepatic impairment. CONCLUSIONS: For patients with variceal bleeding and a small liver volume, the 6-mm shunt significantly reduced the incidence of overt HE, protected perioperative liver function, and did not affect stent patency or rebleeding rate. CLINICAL RELEVANCE STATEMENT: For patients with variceal bleeding with small liver volume, the 6-mm transjugular intrahepatic portosystemic shunt (TIPS) significantly reduced the incidence of overt hepatic encephalopathy after TIPS, protected perioperative liver function, and did not affect stent patency and rebleeding rate. KEY POINTS: • A strategy for the creation of a 6-mm transjugular intrahepatic portosystemic shunt for patients with variceal bleeding and a small liver volume was proposed. • The 6-mm transjugular intrahepatic portosystemic shunt significantly reduced the incidence of overt hepatic encephalopathy. • The 6-mm transjugular intrahepatic portosystemic shunt did not affect stent patency or rebleeding rate.

3.
Invest New Drugs ; 41(4): 617-626, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37434023

RESUMO

The purpose of this study was to compare the efficacy and safety of idarubicin-loaded drug-eluting beads-transarterial chemoembolization (IDA-TACE) and epirubicin-loaded drug-eluting beads-TACE (EPI-TACE) in treating hepatocellular carcinoma (HCC). All patients with HCC treated with TACE in our hospital between June 2020 and January 2022 were screened. The included patients were divided into the IDA-TACE group and EPI-TACE group to compare overall survival (OS), time to progression (TTP), objective response rate (ORR), and adverse events. There were 55 patients each in the IDA-TACE and EPI-TACE groups. Compared with the EPI-TACE group, the median TTP in the IDA-TACE group was not significantly different (10.50 vs. 9.23 months; HR 0.68; 95% CI 0.40-1.16; P = 0.154), whereas the survival status in the IDA-TACE group tended to be better (neither achieved; HR 0.47; 95% CI 0.22-1.02; P = 0.055). Based on the Barcelona Clinic Liver Cancer staging system for subgroup analysis, considering stage C patients, the IDA-TACE group performed significantly better in terms of ORR (77.1% vs. 54.3%, P = 0.044), median TTP (10.93 vs. 5.20 months; HR 0.46; 95% CI 0.24-0.89; P = 0.021), and median OS (not achieved vs. 17.80 months; HR 0.41; 95% CI 0.18-0.93; P = 0.033). Considering stage B patients, there were no significant differences between the IDA-TACE and EPI-TACE groups in terms of ORR (80.0% vs. 80.0%, P = 1.000), median TTP (10.20 vs. 11.2 months; HR 1.41; 95% CI 0.54-3.65; P = 0.483), or median OS (neither achieved, HR 0.47; 95% CI 0.04-5.24; P = 0.543). Notably, leukopenia was more common in the IDA-TACE group (20.0%, P = 0.052), and fever was more common in the EPI-TACE group (49.1%, P = 0.010). IDA-TACE was more effective than EPI-TACE in treating advanced-stage HCC and comparable in treating intermediate-stage HCC.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Idarubicina/uso terapêutico , Epirubicina/uso terapêutico , Estudos Retrospectivos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Quimioembolização Terapêutica/efeitos adversos , Resultado do Tratamento , Antibióticos Antineoplásicos/uso terapêutico
4.
J Hepatocell Carcinoma ; 10: 1195-1206, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37521029

RESUMO

Purpose: Combined transarterial chemoembolization (TACE) and Lenvatinib (LEN) treatment (LEN-TACE) has been shown to be beneficial. We aimed to evaluate retrospectively Atezolizumab plus Bevacizumab (Atezo/Bev)-TACE compared with LEN-TACE as a first-line therapy for unresectable HCC. Patients and Methods: From October 2020 to October 2022, data from 98 consecutive HCC patients were analyzed. After propensity score matching, two cohorts of 34 patients who received either Atezo/Bev-TACE or LEN-TACE were studied. We compared overall survival (OS), progression-free survival (PFS), duration of response, objective response rate (ORR) and disease control rate (DCR) based on RECIST 1.1 and mRECIST, as well as safety outcome between the two cohorts. Results: The 6-month and 12-month OS rates were 85.3% (95% CI 73.5-97.0) and 75.4% (95% CI 53.6-85.7) in the Atezo/Bev-TACE group, and 88.2% (95% CI 76.5-97.1) and 79.2% (95% CI 63.6-90.9) in the LEN-TACE group, respectively. The hazard ratio for death in the Atezo/Bev-TACE group compared to the LEN-TACE group was 1.09 (95% CI 0.47-2.51; P = 0.837). The median PFS was 7.03 months (95% CI 3.89-10.17) in the Atezo/Bev-TACE group and 6.03 months (95% CI 0-14.14) in the LEN-TACE group (HR 1.21; 95% CI 0.66-2.21; P = 0.545). No significant difference in ORR and DCR between the two groups was observed either according to RECIST 1.1 or mRECIST standards. Incidence rates of hand-foot skin reaction (35.3% vs 5.9%, P = 0.003) and proteinuria (17.9% vs 2.9%, P = 0.046) were significantly higher in the LEN-TACE group. Conclusion: Atezo/Bev-TACE and LEN-TACE showed comparable efficacy and safety as first-line therapies for unresectable HCC patients.

5.
Front Plant Sci ; 14: 1165582, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37223800

RESUMO

Introduction: Drought stress is one of the most serious abiotic stresses leading to crop yield reduction. Due to the wide range of planting areas, the production of maize is particularly affected by global drought stress. The cultivation of drought-resistant maize varieties can achieve relatively high, stable yield in arid and semi-arid zones and in the erratic rainfall or occasional drought areas. Therefore, to a great degree, the adverse impact of drought on maize yield can be mitigated by developing drought-resistant or -tolerant varieties. However, the efficacy of traditional breeding solely relying on phenotypic selection is not adequate for the need of maize drought-resistant varieties. Revealing the genetic basis enables to guide the genetic improvement of maize drought tolerance. Methods: We utilized a maize association panel of 379 inbred lines with tropical, subtropical and temperate backgrounds to analyze the genetic structure of maize drought tolerance at seedling stage. We obtained the high quality 7837 SNPs from DArT's and 91,003 SNPs from GBS, and a resultant combination of 97,862 SNPs of GBS with DArT's. The maize population presented the lower her-itabilities of the seedling emergence rate (ER), seedling plant height (SPH) and grain yield (GY) under field drought conditions. Results: GWAS analysis by MLM and BLINK models with the phenotypic data and 97862 SNPs revealed 15 variants that were significantly independent related to drought-resistant traits at the seedling stage above the threshold of P < 1.02 × 10-5. We found 15 candidate genes for drought resistance at the seedling stage that may involve in (1) metabolism (Zm00001d012176, Zm00001d012101, Zm00001d009488); (2) programmed cell death (Zm00001d053952); (3) transcriptional regulation (Zm00001d037771, Zm00001d053859, Zm00001d031861, Zm00001d038930, Zm00001d049400, Zm00001d045128 and Zm00001d043036); (4) autophagy (Zm00001d028417); and (5) cell growth and development (Zm00001d017495). The most of them in B73 maize line were shown to change the expression pattern in response to drought stress. These results provide useful information for understanding the genetic basis of drought stress tolerance of maize at seedling stage.

6.
Nat Commun ; 14(1): 291, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36653348

RESUMO

The slow redox kinetics of polysulfides and the difficulties in decomposition of Li2S during the charge and discharge processes are two serious obstacles to the practical application of lithium-sulfur batteries. Herein, we construct the Fe-Co diatomic catalytic materials supported by hollow carbon spheres to achieve high-efficiency catalysis for the conversion of polysulfides and the decomposition of Li2S simultaneously. The Fe atom center is beneficial to accelerate the discharge reaction process, and the Co atom center is favorable for charging process. Theoretical calculations combined with experiments reveal that this excellent bifunctional catalytic activity originates from the diatomic synergy between Fe and Co atom. As a result, the assembled cells exhibit the high rate performance (the discharge specific capacity achieves 688 mAh g-1 at 5 C) and the excellent cycle stability (the capacity decay rate is 0.018% for 1000 cycles at 1 C).

7.
J Vasc Interv Radiol ; 34(5): 768-776, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36581194

RESUMO

PURPOSE: To compare the clinical results of microwave ablation (MWA) between patients downstaged to Barcelona Clinic Liver Cancer (BCLC) Stage A with transarterial chemoembolization (TACE) and those initially classified as BCLC Stage A. MATERIALS AND METHODS: From January 2012 to May 2017, 1,087 patients were reviewed retrospectively using propensity score matching (1:1): 86 patients underwent MWA as a curative treatment after downstaging to BCLC Stage A by TACE (downstaging group) and 86 patients initially classified as BCLC Stage A underwent MWA (control group). The overall survival (OS) and disease-free survival (DFS) between the 2 groups were compared. RESULTS: The 1-, 3-, and 5-year OS rates were 95.3%, 79.1%, and 58.1%, respectively, in the downstaging group and 93.0%, 81.4%, and 61.6%, respectively, in the control group (hazard ratio [HR], 0.75; 95% CI, 0.50-1.13; P = .162). The 1-, 3-, and 5-year DFS rates were 80.2%, 50.0%, and 24.4%, respectively, in the downstaging group and 77.9%, 52.3%, and 27.9%, respectively, in the control group (HR, 1.08; 95% CI, 0.76-1.53; P = .678). No significant differences were found in OS and DFS. CONCLUSIONS: The long-term prognosis in patients with HCC who underwent MWA after downstaging to BCLC Stage A using TACE was similar to that in patients with initial BCLC Stage A.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Micro-Ondas/efeitos adversos , Estadiamento de Neoplasias , Quimioembolização Terapêutica/métodos , Resultado do Tratamento
8.
J Colloid Interface Sci ; 633: 155-165, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36436348

RESUMO

The Gibbs free energy of hydrogen adsorption at the edge of molybdenum disulfide (MoS2) is close to that of Pt, meaning that MoS2 is the best candidate to replace Pt-based materials. However, easy agglomeration between layers to mask active sites, lack of catalytic activity in the basal planes, and poor electronic conductivity make MoS2 exhibit dissatisfactory hydrogen evolution reaction (HER) catalytic performance. Here, we successfully construct a van der Waals heterostructure stacked alternately with Mo(SSe)2-x and graphene (Mo(SSe)2-x/G) to enhance its catalytic ability. The introduction of Se into MoS2 and the thermal treatment induce the sample to generate more anion vacancies. Theoretical and experimental results demonstrate the constructed van der Waals heterostructure, the introduced Se element, and the increased anion vacancies are in favor of promoting the number of active sites and improving the electronic conductivity of the catalyst. Therefore, Mo(SSe)2-x/G exhibits superior HER catalytic performance (the overpotentials of 137 mV and 136 mV at a current of 10 mA cm-2) and long-term stabilities (>90 h and 140 h at a current density of 20 mA cm-2) in both acidic and alkaline media.

9.
Huan Jing Ke Xue ; 43(6): 3016-3026, 2022 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-35686771

RESUMO

As an important carrier of human activities, the spatial type of land use has an important impact on the surface water environment. Taking the Ruoergai wetland as an example, based on object-oriented remote sensing interpretation of land use types combined with water quality examination data, this study analyzed the impact and driving mechanism of land use types at different scales on the surface water environment at the small watershed and buffer scale. ① It was found that the water quality of the Ruoergai wetland could been classified as water grade V, and it was slightly eutrophic as a whole. The main pollutants were total nitrogen(TN) and phosphorus(TP), and the pollution originated from domestic sewage and grazing. ② The environmental quality of surface water was closely related to land use types. There was a negative correlation between chemical oxygen demand(COD) and the proportion of water area, a positive correlation between TN and the proportion of swamp area, and a negative correlation between total TP. ③ There was a significant correlation between spatial land use types at different scales and surface water environment. The land use type within a buffer of 1000 m had the highest interpretation degree for all factors, the land use type within a buffer of 200 m had the greatest interpretation degree for COD, the land use type within a buffer of 500 m zone had the greatest interpretation degree for TP and TN, and the land use type within a buffer of 800 m had the greatest explanation for Chl-a. The results of this study showed that the Ruoergai wetland wetland had a certain purification effect on pollutants and eutrophication. However, different land use types had different effects on different pollutants. The water body had a purification effect on Fe2+, COD, and Chl-a, and the swamp had a purification effect on TP but a cumulative effect on TN. Thus, the small-buffer zone(≤ 1000 m) land use type should be controlled, the water body and swamp areas should be controlled, the self-purification capacity of wetland waters should be improved, and the surface water environment of the Ruoergai wetland should be further protected and repaired.


Assuntos
Poluentes Ambientais , Qualidade da Água , Humanos , Nitrogênio/análise , Fósforo/análise , Áreas Alagadas
10.
Chemosphere ; 294: 133739, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35085610

RESUMO

Degradation experiments are conducted to specifically compare the degradation of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) by aerobic and anaerobic strains isolated from real e-waste sites contaminated by BDE-47. The effect of carbon sources, inducers and surfactants on the degradation was examined to strengthen such a comparison. An aerobic strain, B. cereus S1, and an anaerobic strain, A. faecalis S4, were obtained. The results indicated that BDE-47 could be used as the sole carbon source by B. cereus S1 and A. faecalis S4 under aerobic and anaerobic conditions, respectively. The degradation of BDE-47 by B. cereus S1 and A. faecalis S4 was illustrated a first-order kinetics process obtaining a removal efficiency of 61.6% and 51.6% with a first-order rate constant of 0.0728 d-1 and 0.0514 d-1, and corresponding half-life of 8.7 d and 13.5 d, respectively. The addition of carbon sources (yeast extract, glucose, acetic acid and ethanol) and inducers (2,4-dichlorophenol, bisphenol A and toluene) promoted BDE-47 degradation by both B. cereus S1 and A. faecalis S4 under aerobic and anaerobic conditions, while hydroquinone as the inducer inhibited the degradation. All of the surfactants tested (CTAB, Tween 80, Triton X-100, rhamnolipid and SDS) showed inhibitory effect. BDE-47 degradation by B. cereus S1 under aerobic condition was more efficient than A. faecalis S4 under anaerobic condition whether with or without the additives. The results of the study indicated that in the field sites contaminated by BDE-47, the aerobic condition can be more favorable for BDE-47 removal and the degradation can be further enhanced by applying suitable carbon sources and inducers.


Assuntos
Resíduo Eletrônico , Anaerobiose , Bactérias/metabolismo , Bactérias Anaeróbias/metabolismo , Biodegradação Ambiental , Éteres Difenil Halogenados/metabolismo , Éteres Difenil Halogenados/farmacologia
11.
Materials (Basel) ; 16(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36614486

RESUMO

As a new type of energy-containing material, Ammonium dinitramide based liquid propellant has the advantages of being green, having low toxicity, good stability, and high safety performance. Traditional catalytic combustion methods require preheating of the catalytic bed and deactivation of the catalytic particles at high temperatures, while microwave ignition methods can effectively solve these problems. To study the combustion characteristics of ADN-based liquid propellants during microwave ignition, the influence of microwave power and gas flow rates on the combustion process are analyzed using experimental methods. A high-speed camera was used to observe the enhanced effects of microwave power and gas flow on plasma and flame. Combined with temperature measurement, the combustion process of ADN-based liquid propellants under the action of plasma was analyzed. The combustion process in the presence of microwaves was observed by comparing parameters such as flame length, flame temperature, and radical intensity. Those results show that, with the increase in microwave power, the luminous burning area of the flame grows significantly. The microwave power is increased by 250 W each, and the flame jet length is increased by nearly 20%. The increase in microwave power also leads to an increase in propellant combustion temperature, however, this increase gradually slows down. At a gas flow rate of 20 L/min, the ADN-based liquid propellant showed the best combustion performance with a maximum jet length of 14.51 cm and an average jet length increase of approximately 85.9% compared to 14 L/min. Too much gas flow rate will hinder the development of the jet, while the high-velocity airflow will have a cooling effect on the flame temperature. The results provide a basis for the specific parameter design of microwave ignition and promote the application of ADN-based liquid propellants in the aerospace field.

12.
J Neurointerv Surg ; 14(10): 1022-1026, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34782398

RESUMO

BACKGROUND: Higher extended Thrombolysis In Cerebral Infarction (eTICI) grades are associated with better clinical outcomes after endovascular treatment (EVT) for proximal intracranial occlusion of the anterior circulation. However, the relationship between eTICI grade and outcomes after EVT in patients with acute basilar artery occlusion (BAO) remains unclear. We aimed to explore which eTICI category was the cut-off correlating with better clinical outcomes in patients with BAO undergoing EVT. METHODS: We included patients treated via EVT from the BASILAR study. Multivariable logistic regression analyses were performed to assess the impact of eTICI grades on 90-day favorable functional outcomes, defined as a modified Rankin Scale (mRS) score of 0-3. Other outcomes were functional independence (mRS 0-2), all-cause mortality, and symptomatic intracranial hemorrhage. RESULTS: Among 647 patients treated with EVT, 127 (19.6%), 128 (24.5%), 110 (21.1%), and 282 (54%) patients achieved eTICI grades of 0-2a, 2b, 2c, and 3, respectively. Compared with eTICI grades 0-2a, higher rates of favorable functional outcomes (adjusted OR (aOR) 2.96, 95% CI 1.33 to 6.57, and aOR 7.40, 95% CI 3.63 to 15.09, respectively) were observed for grades 2c and 3, not 2b (aOR 1.93, 95% CI 0.86 to 4.36). The risks of mortality and symptomatic intracranial hemorrhage were also lower for eTICI grades 2c and 3 than for grades 0-2a. CONCLUSIONS: An eTICI grade of 2c/3 may be a target for successful reperfusion after EVT in patients with acute BAO; however, further studies with larger sample sizes and clinical trials are needed.


Assuntos
Arteriopatias Oclusivas , Procedimentos Endovasculares , Acidente Vascular Cerebral , Arteriopatias Oclusivas/terapia , Artéria Basilar/diagnóstico por imagem , Angiografia Cerebral , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/etiologia , Infarto Cerebral/terapia , Procedimentos Endovasculares/efeitos adversos , Humanos , Hemorragias Intracranianas/diagnóstico por imagem , Hemorragias Intracranianas/etiologia , Estudos Retrospectivos , Acidente Vascular Cerebral/terapia , Trombectomia , Terapia Trombolítica , Resultado do Tratamento
13.
J Neurointerv Surg ; 14(11): 1073-1076, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34732534

RESUMO

BACKGROUND: The best anesthetic management strategy for patients with acute large vessel occlusion treated with mechanical thrombectomy (MT) remains uncertain. Most studies have focused on anterior-circulation stroke caused by large artery occlusion. Nevertheless, limited data are available on the appropriate choice of anesthetic for acute basilar artery occlusion (BAO). We aimed to investigate the effect of anesthetic method on clinical outcomes in patients with BAO undergoing MT. METHODS: Patients undergoing MT for acute BAO in the BASILAR registry (Acute Basilar Artery Occlusion Study) were included. We divided patients into three groups according to the anesthetic technique used during MT: general anesthesia (GA), local anesthesia (LA), and conscious sedation (CS). Propensity score matching was performed to achieve baseline balance. RESULTS: 639 patients were included. GA was used in 257 patients (40.2%), LA was used in 250 patients (39.1%), and CS was used in 132 patients (20.7%). After 1:1 matching, favorable outcome, mortality, and hemorrhagic transformation rates, as well as modified Rankin Scale (mRS) score at 90 days, did not differ between the GA, LA, and CS groups. CONCLUSIONS: The choice of anesthetic strategy, GA, LA, or CS, did not affect the clinical outcomes of patients with acute BAO treated with MT in the BASILAR registry.


Assuntos
Anestésicos , Arteriopatias Oclusivas , Procedimentos Endovasculares , Acidente Vascular Cerebral , Arteriopatias Oclusivas/etiologia , Artéria Basilar , Procedimentos Endovasculares/métodos , Humanos , Estudos Retrospectivos , Acidente Vascular Cerebral/terapia , Trombectomia/métodos , Resultado do Tratamento
14.
Nanomicro Lett ; 14(1): 40, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34950984

RESUMO

Precisely regulating of the surface structure of crystalline materials to improve their catalytic activity for lithium polysulfides is urgently needed for high-performance lithium-sulfur (Li-S) batteries. Herein, high-index faceted iron oxide (Fe2O3) nanocrystals anchored on reduced graphene oxide are developed as highly efficient bifunctional electrocatalysts, effectively improving the electrochemical performance of Li-S batteries. The theoretical and experimental results all indicate that high-index Fe2O3 crystal facets with abundant unsaturated coordinated Fe sites not only have strong adsorption capacity to anchor polysulfides but also have high catalytic activity to facilitate the redox transformation of polysulfides and reduce the decomposition energy barrier of Li2S. The Li-S batteries with these bifunctional electrocatalysts exhibit high initial capacity of 1521 mAh g-1 at 0.1 C and excellent cycling performance with a low capacity fading of 0.025% per cycle during 1600 cycles at 2 C. Even with a high sulfur loading of 9.41 mg cm-2, a remarkable areal capacity of 7.61 mAh cm-2 was maintained after 85 cycles. This work provides a new strategy to improve the catalytic activity of nanocrystals through the crystal facet engineering, deepening the comprehending of facet-dependent activity of catalysts in Li-S chemistry, affording a novel perspective for the design of advanced sulfur electrodes.

15.
ACS Nano ; 15(10): 16515-16524, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34590820

RESUMO

Lithium-sulfur (Li-S) batteries are one of the most promising candidates for next-generation energy storage systems because of their high theoretical energy density. However, the shuttling behavior and sluggish conversion kinetics of lithium polysulfides (LiPSs) limit their practical application. Herein, B-doped MoS2 nanosheets are synthesized on carbon nanotubes (denoted as CNT@MoS2-B) to function as catalysts to boost the performance of Li-S batteries. The poor catalytic performance of the pristine MoS2 is revealed to be the result of unsuitable orbital orientation of the basal plane, which hinders the orbital overlap with sulfur species. B in CNT@MoS2-B is sp3 hybridized, and it has a vacant σ orbital perpendicular to the basal plane, which can maximize the head-on orbital overlap with S. The incorporation of B significantly increases the reactivity of MoS2 basal plane, which can facilitate the kinetics of Li2S formation and dissolution. With these merits, the S/CNT@MoS2-B cathodes deliver high rate capability and outstanding cycling stability, holding great promise for both scientific research and practical application. This work affords fresh insights for developing effective catalysts to accelerate LiPS conversion.

16.
Small ; 17(42): e2102962, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34520126

RESUMO

Polysulfide shuttling and sluggish sulfur redox kinetics hinder the cyclability and rate capability of lithium-sulfur (Li-S) batteries. The intrinsic redox kinetics of sulfur cathodes strongly depends on the interaction between catalysts and sulfur species. Herein, N-doped CoTe2 is proposed as an effective dual-anchoring electrocatalyst, which can simultaneously bind Li and S atoms in lithium polysulfides via ionic Te-Li/N-Li bonding and coordinate covalent Co-S bonding. The incorporated N not only serves as enhanced lithiophilic site, but also an agent to improve the sulfiphilicity of the Co site as revealed by a series of experimental and computational results. Benefiting from these superiorities, the use of N-doped CoTe2 as a catalytic interlayer enables efficient operation of Li-S batteries in terms of impressive rate capability of 758 mAh g-1 at 4 C and very low capacity decay of 0.021% per cycle over 1000 cycles. The material and strategy demonstrated in this work may open the door toward developing more advanced Li-S electrocatalysts.

17.
Front Public Health ; 9: 635818, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34055713

RESUMO

Background: From the traditional Chinese medicine (TCM) constitution theory perspective, the phlegm-dampness constitution is thought to be closely related to the occurrence of non-alcoholic fatty liver disease (NAFLD). However, this viewpoint still lacks rigorous statistical evidence. This study aimed to test the association between the phlegm-dampness constitution and NAFLD. Methods: We conducted a cross-sectional study. Participants were residents living in Chengdu, China, undergoing health checkups at the health management center of Affiliated Hospital of Chengdu University of Traditional Chinese Medicine between December 2018 and September 2020. TCM constitution type was diagnosed by DAOSH four examinations instrument, NAFLD was diagnosed according to the liver ultrasonography and medical history. Multivariate logistic regression and propensity score matching (PSM) were used to analyze a total of 1,677 qualified data. Results: 1,037 participants had biased constitution(s), 67.8% of which had mixed constitutions (with at least two constitutions). Among 1,677 participants, the phlegm-dampness constitution was associated with the yang-deficiency, yin-deficiency, dampness-heat, qi-depression, and blood-stasis constitutions. The correlation coefficients were 0.11, 0.32, 0.42, 0.20, 0.14, respectively. Between the phlegm-dampness constitution and NAFLD, the odds ratio (OR) and the 95% confidence interval (CI) was 2.05 (1.57-2.69) in the crude model. After adjusting for age, gender, Body mass index (BMI), other biased constitutions, smoking, high blood pressure, diabetes, and dyslipidemia, the OR reduced to 1.51 (1.04-2.18). The associations of seven other biased TCM constitutions and NAFLD were not statistically significant in the fully adjusted model. The PSM analysis showed consistent results with the logistic regression. Conclusions: Among eight biased TCM constitutions, the phlegm-dampness constitution is independently associated with NAFLD. We speculate the phlegm-dampness constitution is a risk factor of NAFLD. Longitudinal studies are needed to confirm this causal relationship in the future. In addition, inconsistent with some TCM practitioners' experience, we disagree that the blood-stasis constitution is associated with NAFLD.


Assuntos
Medicina Tradicional Chinesa , Hepatopatia Gordurosa não Alcoólica , Constituição Corporal , China/epidemiologia , Estudos Transversais , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico
18.
iScience ; 24(2): 101982, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33521596

RESUMO

Plasmonic metal nanostructures (PMNs) are characterized by the plasmon oscillation of conduction band electron in response to external radiation, enabling strong light absorption and scattering capacities and near-field amplification. Owing to these enhanced light-matter interactions, PMNs have garnered extensive research interest in the past decades. Notably, a growingly large number of reports show that the energetics and kinetics of chemical transformations on PMNs can be modified upon photoexcitation of their plasmons, giving rise to a new paradigm of manipulating the reaction rate and selectivity of chemical reactions. On the other hand, there is urgent need to achieve clear understanding of the mechanism underlying the photo-mediated chemical transformations on PMNs for unleashing their full potential in converting solar energy to chemicals. In this perspective, we review current fundamental concepts of photo-mediated chemical transformations executed at PMNs. Three pivotal mechanistic questions, i.e., thermal and nonthermal effects, direct and indirect charge transfer processes, and the specific impacts of plasmon-induced potentials, are explored based on recent studies. We highlight the critical aspects in which major advancements should be made to facilitate the rational design and optimization of photo-mediated chemical transformations on PMNs in the future.

19.
Inorg Chem ; 60(3): 1491-1498, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33464052

RESUMO

In recent years, low-dimensional lead halides have emerged as some of most attractive photoelectric materials due to their intrinsic broadband emissions with a potential application in white-light emitting diodes. To achieve the desired performance, tremendous research has emphasized the modulation of inorganic components as optical centers; however, less work has paid attention to the direct contribution of the organic components. Herein, we successfully assembled two new hybrid lead halides of [H2BPP]Pb2X6 (X = Br, 1, and Cl, 2) containing one-dimensional double [Pb2X6]2- chains using optically active 1,3-bis(4-pyridyl)-propane (BPP) as an organic cation. Under UV-light excitation, compounds 1 and 2 exhibit broadband yellowish-green emissions, which were verified by promising photoluminescence quantum efficiencies (PLQEs) of 8.10% and 4.84%, respectively. The broadband light emissions are derived from the combination of dual higher-energy blue and lower-energy yellow light spectra, which can be attributed to the individual contributions of the organic and inorganic components, respectively, according to the time-resolved and temperature-dependent emission spectra as well as theoretical calculations. This work proves the great contribution of organic components to the photophysical properties and provides a new design strategy to realize broadband light emission by rationally combining the dual-emitting properties of different assembly blocks.

20.
Chem Commun (Camb) ; 56(92): 14467-14470, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33147303

RESUMO

Unique Fe and N co-doped multi-walled carbon nanotubes are designed to efficiently catalyze the oxygen reduction reaction (ORR). The preparation processes involve surface functionalization, subsequent wet impregnation and final thermal fixation of Fe-Nx species. The catalyst achieved outstanding alkaline ORR performance with a very positive half-wave potential (∼0.91 V). Theoretical calculations show that the carbon layer below the active Fe-Nx sites is beneficial to the ORR.

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