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1.
Muscle Nerve ; 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32129891

RESUMO

INTRODUCTION: We investigated the feasibility of motor unit number index (MUNIX) in quantitatively assessing motor root lesions and tracking different treatment outcomes in lumbosacral radiculopathy (LR). METHODS: Bilateral MUNIX was recorded from the abductor hallucis, extensor digitorum brevis, and tibialis anterior in 44 normal controls and 108 patients with LR, and this was repeated approximately 12 months after treatment in 60 patients with LR. RESULTS: More abnormalities were observed when side-to-side differences of MUNIX measurements were used to evaluate LR (P < .05). Motor unit number index measurements worsened without progression of muscle weakness after conservative treatment, and MUNIX measurements improved with or without increased muscle strength after surgical treatment (P < .05). DISCUSSION: Motor unit number index may identify a specific L5 or S1 motor root lesion even before muscle weakness occurs, especially when side-to-side differences are used. Changes in MUNIX were larger than those in motor function measures after treatments for LR.

2.
Orthop Surg ; 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32159285

RESUMO

OBJECTIVES: To investigate the contact stress and the contact area o tibial inserts and bushings with respect to different congruency designs in a spherical center axis and rotating bearing hinge knee prosthesis under gait cycle loading conditions using finite element analysis. METHODS: Nine prostheses with different congruency (different degrees of tibiofemoral conformity and different distances between the spherical center and the bushing) designs were developed with the same femoral and tibial components. The models were transferred to finite element software. The peak contact stresses and contact areas on tibial inserts and bushings under the gait cycle loading conditions were investigated and compared. RESULTS: For tibial insert, the peak contact stress was the highest in the low conformity-long group (61.4486 MPa), and it was 1.88 times higher than that in the group with the lowest stress (moderate conformity-short group, 32.754 MPa). The contact area was the largest in the low conformity-long group (420.485 mm2 ), and it was 1.19 times larger than that in the group with the smallest area (moderate conformity-middle group, 352.332 mm2 ). For bushing, the peak contact stress was the highest in the high conformity-long group (72.8093 MPa), and it was 3.21 times higher than that in the group with the lowest stress (high conformity-short group, 22.6928 MPa). The contact area was the largest in the low conformity-short group (2.41 mm2 ), and it was 2.27 times larger than that in the group with the smallest area (high conformity-middle group, 1.063 mm2 ). CONCLUSION: The results of our study showed that the congruency of the tibiofemoral surface and bushing surface should be considered carefully in the design of the spherical center axis and rotating bearing hinge knee prosthesis. Different levels of contact performance were observed with different congruency designs. In addition, the influence of contact stress and contact area on the polyethylene wear of rotating hinge knee prostheses should be confirmed with additional laboratory tests.

3.
PLoS One ; 15(3): e0229899, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32134997

RESUMO

OBJECTIVE: To investigate that whether an association between marital status and the female breast cancer risk exists. METHODS: The MEDLINE, EMBASE and PsycINFO databases were searched from their inception to July 2019. The Newcastle-Ottawa Scale was used to rate the methodological quality of included studies. Study data were pooled using random-effects meta-analyses to compare the breast cancer risk between unmarried, widowed, divorced or lifelong single women and married women. This study is registered with PROSPERO (number CRD42018112368). RESULTS: Forty-nine publications were included in the meta-analysis. Compared with married women, unmarried and lifelong single women had an elevated risk of breast cancer, and the pooled ORs of case-control studies were 1.20 (95% CI: 1.07 to 1.35) and 1.24 (95% CI: 1.05 to 1.45), respectively. In the subgroup analyses under these two comparisons, hospital-based estimates and multivariate-adjusted estimates demonstrated a strong association, while population-based estimates and age-adjusted estimates produced nonsignificant results. The pooled OR of cohort studies examining the effect of being a lifelong single woman was 1.10 (95% CI: 1.04 to 1.16). Heterogeneity was moderate to substantial across case-control studies (I2: 46% to 82%), which may be partially explained by differences in geographic regions, publication years and control types. Possible publication bias was indicated by the funnel plot and Egger's test (P = 0.03). CONCLUSIONS: Marital status may correlate with the risk of developing female breast cancer. However, suboptimal selection of controls, insufficient exploration of confounding effects, inadequate ascertainment of marital status, and possible publication bias may have limited the quality of the available evidence. Overall, conclusions that marital status is an independent risk factor for breast cancer could not be drawn, and further prospective rigorous cohort studies are warranted.

4.
JAMA Surg ; 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32211839
5.
Yi Chuan ; 42(2): 212-221, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32102777

RESUMO

An ongoing outbreak of a novel coronavirus infection in Wuhan, China since December 2019 has led to 31,516 infected persons and 638 deaths across 25 countries (till 16:00 on February 7, 2020). The virus causing this pneumonia was then named as the 2019 novel coronavirus (2019-nCoV) by the World Health Organization. To promote the data sharing and make all relevant information of 2019-nCoV publicly available, we construct the 2019 Novel Coronavirus Resource (2019nCoVR, https://bigd.big.ac.cn/ncov). 2019nCoVR features comprehensive integration of genomic and proteomic sequences as well as their metadata information from the Global Initiative on Sharing All Influenza Data, National Center for Biotechnology Information, China National GeneBank, National Microbiology Data Center and China National Center for Bioinformation (CNCB)/National Genomics Data Center (NGDC). It also incorporates a wide range of relevant information including scientific literatures, news, and popular articles for science dissemination, and provides visualization functionalities for genome variation analysis results based on all collected 2019-nCoV strains. Moreover, by linking seamlessly with related databases in CNCB/NGDC, 2019nCoVR offers virus data submission and sharing services for raw sequence reads and assembled sequences. In this report, we provide comprehensive descriptions on data deposition, management, release and utility in 2019nCoVR, laying important foundations in aid of studies on virus classification and origin, genome variation and evolution, fast detection, drug development and pneumonia precision prevention and therapy.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Bases de Dados Genéticas , Disseminação de Informação , China , Coronavirus , Genômica , Humanos , Proteômica
6.
Adv Mater ; : e1906972, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31984566

RESUMO

Developing efficient electrocatalysts for alkaline water electrolysis is central to substantial progress of alkaline hydrogen production. Herein, a Ni5 P4 electrocatalyst incorporating single-atom Ru (Ni5 P4 -Ru) is synthesized through the filling of Ru3+ species into the metal vacancies of nickel hydroxides and subsequent phosphorization treatment. Electron paramagnetic resonance spectroscopy, X-ray-based measurements, and electron microscopy observations confirm the strong interaction between the nickel-vacancy defect and Ru cation, resulting in more than 3.83 wt% single-atom Ru incorporation in the obtained Ni5 P4 -Ru. The Ni5 P4 -Ru as an alkaline hydrogen evolution reaction catalyst achieves low onset potential of 17 mV and an overpotential of 54 mV at a current density of 10 mA cm-2 together with a small Tafel slope of 52.0 mV decade-1 and long-term stability. Further spectroscopy analyses combined with density functional theory calculations reveal that the doped Ru sites can cause localized structure polarization, which brings the low energy barrier for water dissociation on Ru site and the optimized hydrogen adsorption free energy on the interstitial site, well rationalizing the experimental reactivity.

7.
J Environ Manage ; 258: 110052, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31929078

RESUMO

The atmospheric pollution has been the public attention in recent years. In order to better coordinate economic development and atmospheric environmental management, China introduced the concept of atmospheric environmental capacity (AEC). The remaining atmospheric environmental capacity (RAEC) calculated by existing atmospheric pollution sources and AEC is an important basis for regional development and environmental protection. The RAEC of the high-pollution risk suburb of Chengdu in 2015 was estimated by the single-box model and analyzed on multiple time scales. The results show that the RAEC of SO2 and NO2 in this region is 3299 t/a and 2849 t/a, respectively under the annual time scale. However, in the daily time scale, the RAEC of NO2 is negative for 3 days, that is, there are 3 days with serious air pollution. Therefore, it is not appropriate to plan the industrial area only by relying on annual RAEC. Especially, RAEC displays inter-seasonal and monthly variability. On the one hand, in plain areas with low wind speed and little change in wind direction, achieving the prediction of atmospheric mixing layer height could give early warning of atmospheric pollution events. On the other hand, different management measures are taken on different time scales. On a long timescale, the regional energy structure should be optimized. On seasonal and monthly time scales, the production plans should be adapted to RAEC. On the daily time scale, it mainly deals with the serious atmospheric pollution accident timely.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , China , Monitoramento Ambiental , Material Particulado , Estações do Ano
8.
Nanotechnology ; 31(20): 205703, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31995540

RESUMO

Superlubricity between a cone-shaped (sharp) silicon tip and graphite remains a challenge in the nanotribology field. In this paper, an efficient method of achieving superlubricity between a cone-shaped silicon tip and graphite was proposed. Graphite nanoflakes were transferred onto the silicon tip by repeatedly rubbing against the scratches produced by nanolithography on a graphite surface. The superlubricity between the graphite nanoflakes-wrapped tip and highly oriented pyrolytic graphite (HOPG) was attained, and the friction coefficient was reduced to 0.0007. At low normal loads, the frictional force was small and showed a strong correlation with the sliding angle, but as the normal load increased, this dependence gradually decreased. It was firstly found that the transferred graphite nanoflakes on the contact zone of the silicon tip could be transformed into amorphous carbon layers induced by the shear force and high pressure during the superlubricity test process.

9.
Int J Biol Macromol ; 142: 288-297, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31593728

RESUMO

This work tailored a promising two-step pretreatment, i.e., liquid hot water extraction followed by mild acidic deep eutectic solvents pretreatment for clean lignocellulose fractionation while enhancing cellulose reactivity for its subsequent utilization. The abilities of three acidic deep eutectic solvents (formic acid-, acetic acid- and lactic acid-choline chloride) to selectively extract poplar wood lignin and enhance cellulose reactivity were comparatively assessed. Results showed that rather high lignin selectivity of 6.3-7.9 was obtained while the available area and porosity of the resulting cellulose were significantly increased. The resulting cellulose pulps exhibited comparable chemical reactivity to commercial bleached Kraft pulp when cellulose acetate was selected as testing cellulose derivative for demonstrating purpose, showing their great promise for high-value use. It was proposed that the unique ionic properties of these acidic deep eutectic solvents were responsible for their selective lignin removal and cellulose swelling/deconstruction to enhance cellulose chemical reactivity.

10.
World J Surg ; 44(1): 171-178, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31552458

RESUMO

BACKGROUND: Although a greater depth of tumor invasion is correlated with a poorer prognosis in esophageal squamous cell carcinoma (ESCC), it remains controversial whether T2 ESCC should be subclassified by circular and longitudinal muscle invasion. We conducted a multicenter retrospective study to evaluate the relationship between the depth of invasion and long-term outcome and to identify the clinical significance of subclassifying T2 ESCC. METHODS: Patients with T2 ESCC who underwent esophagectomy at two different institutes between January 2009 and December 2017 were analyzed retrospectively. ESCC with circular and longitudinal muscle invasion was defined as T2 circular and T2 longitudinal ESCC, respectively. Survival outcomes and risk factors for lymph node metastasis (LNM) were evaluated by univariate and multivariate analyses. In addition, data from stage T1b ESCC cases during the same period were retrieved for use as a comparison cohort to evaluate the prognostic significance of the T2 substage. RESULTS: A total of 536 T2 ESCC patients were eligible, and 192 (36%) patients developed LNM. No significant difference was found in general characteristics between the T2 circular and T2 longitudinal ESCC groups (n = 219 and n = 317, P > 0.05), except for tumor location (P = 0.02). The T2 substage was not significantly correlated with survival on univariate or multivariate analysis (P = 0.30 and P = 0.34, respectively). Multivariate analysis also indicated that the T2 substage was not an independent risk factor for LNM (P = 0.15). When patients with stage T1b ESCC were considered, their survival time was significantly different from that of patients with T2 circular and T2 longitudinal disease (P = 0.01). CONCLUSIONS: The depth of tumor invasion into the circular and longitudinal muscle layers in T2 ESCC does not affect the prognosis or risk of LNM.

12.
Plant Biotechnol J ; 18(1): 129-140, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31141279

RESUMO

Development of marker-free and transgene insertion site-defined (MFTID) transgenic plants is essential for safe application of transgenic crops. However, MFTID plants have not been reported for wheat (Triticum aestivum). Here, we prepared a RNAi cassette for suppressing lipoxygenase (LOX) gene expression in wheat grains using a double right border T-DNA vector. The resultant construct was introduced into wheat genome via Agrobacterium-mediated transformation, with four homozygous marker-free transgenic lines (namely GLRW-1, -3, -5 and -8) developed. Aided by the newly published wheat genome sequence, the T-DNA insertion sites in GLRW-3 and GLRW-8 were elucidated at base-pair resolution. While the T-DNA in GLRW-3 inserted in an intergenic region, that of GLRW-8 inactivated an endogenous gene, which was thus excluded from further analysis. Compared to wild -type (WT) control, GLRW-1, -3 and -5 showed decreased LOX gene expression, lower LOX activity and less lipid peroxidation in the grains; they also exhibited significantly higher germination rates and better seedling growth after artificial ageing treatment. Interestingly, the three GLRW lines also had substantially increased contents of several fatty acids (e.g., linoleic acid and linolenic acid) in their grain and flour samples than WT control. Collectively, our data suggest that suppression of grain LOX activity can be employed to improve the storability and fatty acid content of wheat seeds and that the MFTID line GLRW-3 is likely of commercial value. Our approach may also be useful for developing the MFTID transgenic lines of other crops with enhanced grain storability and fatty acid content.

13.
Biosens Bioelectron ; 148: 111827, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31698302

RESUMO

A novel label-free electrochemical aptasensor was fabricated based on a three-dimensional porous electrode (3D-CS/rGO/GCE) for the detection of acetamiprid residues. The sensing signal was generated by the DNA itself. The porous electrode was prepared by electrodeposition in situ and characterized by scanning electron microscope (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). These results indicated that the porous electrode has a uniform nanoporous structure, high active area, and excellent conductivity, leading to improve the transmission efficiency of current signals. The 3D-CS/rGO/GCE was used to increase a load of acetamiprid aptamer on the electrode. Meanwhile, DNA self-assembly strategy was used to further increase the DNA amounts. Thus the electrochemical current was amplified significantly due to increased phosphate group amounts by the above synergistic effect. The determination of acetamiprid residues using square wave voltammetry (SWV) showed good sensitivity, with the linear range from 0.1 pM to 0.1 µM and the detection limit was 71.2 fM. The label-free electrochemical aptasensor was also used to detect acetamiprid residues in tea samples with satisfactory results.

14.
Sci Total Environ ; 701: 134363, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31706211

RESUMO

Heavy metals (e.g., arsenic (As)) and tetracycline (TC) usually coexist in wastewater from livestock farm, whereas the co-adsorption behaviours and mechanisms of As(V) and TC were not well-known. This study investigated the adsorption and co-adsorption of As(V) and TC by a novel yttrium-immobilized-graphene oxide-alginate hydrogel (Y-GO-SA) to explore the adsorption behaviours and mechanisms. The adsorption of As(V) and TC was pH-dependent. The maximum adsorption capacities under the studied concentrations were 273.39 mg/g for As(V), and 477.9 mg/g for TC, respectively, which are much higher than many other reported adsorbents. Furthermore, As(V) adsorption was due to ion exchange between hydroxyl groups and H2AsO42- groups and H-bonds formed with O-containing groups on Y-GO-SA, and the adsorption of TC by Y-GO-SA was mainly ascribed to electrostatic interaction, H-bonds, π - π EDA interaction, n-π EDA interaction, and cation-bonding bridge effects. The co-adsorption of As(V) and TC in binary system indicated that the presence of TC obviously suppressed the adsorption of As(V) due to the competition for active sites, whereas the effect of presence of As(V) on adsorption of TC can be negligible due to the balance contributions from its contrary effects, i.e. enhancement (anion-π interaction) and reduction (competition for Y ions) in TC adsorption. Finally, the hydrogels performed well in the treatment of livestock farm waste water. It can be anticipated that the prepared 3D hydrogel can be used as a powerful adsorbent in the practical application of waste water treatment, owing to its easy separation, high adsorption and good reusability.


Assuntos
Arsênico/química , Grafite/química , Tetraciclina/química , Poluentes Químicos da Água/química , Adsorção , Hidrogéis , Cinética , Eliminação de Resíduos Líquidos , Águas Residuárias/química
15.
Biomolecules ; 9(12)2019 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-31817992

RESUMO

Effective valorization of lignin is crucial to achieve a sustainable, economic and competitive biorefinery of lignocellulosic biomass. In this work, an integrated process was proposed based on a concentrated phosphoric acid plus hydrogen peroxide (PHP) pretreatment to simultaneously facilitate cellulose digestibility and modify lignin as adsorbent. As a dominant constitutor of PHP pretreatment, H2O2 input and its influence on the overall fractionation/lignin modification performance was thoroughly investigated. Results indicated that wheat straw was fractionated more efficiently by increasing the H2O2 input. H2O2 input had a significant influence on the digestibility of the obtained cellulose-rich fraction whereby almost 100.0% cellulose-glucose conversion can be achieved even with only 0.88% H2O2 input. Besides, the adsorption capacity of lignin on MB was improved (74.3 to 210.1 mg g-1) due to the oxidative-modification in PHP pretreatment with H2O2 inputs. Regression analysis indicated that -COOH groups mainly governed the lignin adsorption (R2 = 0.946), which displayed the considerable adsorption capacities for typical cationic substances. This work shows a promising way to integrate the lignin modification concept into the emerging PHP pretreatment process with the dual goal of both cellulose utilization and lignin valorization.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31831423

RESUMO

We propose a deep autoencoder with graph topology inference and filtering to achieve compact representations of unorganized 3D point clouds in an unsupervised manner. Many previous works discretize 3D points to voxels and then use lattice-based methods to process and learn 3D spatial information; however, this leads to inevitable discretization errors. In this work, we try to handle raw 3D points without such compromise. The proposed networks follow the autoencoder framework with a focus on designing the decoder. The encoder of the proposed networks adopts similar architectures as in PointNet, which is a well-acknowledged method for supervised learning of 3D point clouds. The decoder of the proposed networks involves three novel modules: the folding module, the graph-topology-inference module, and the graph-filtering module. The folding module folds a canonical 2D lattice to the underlying surface of a 3D point cloud, achieving coarse reconstruction; the graph-topology-inference module learns a graph topology to represent pairwise relationships between 3D points, pushing the latent code to preserve both coordinates and pairwise relationships of points in 3D point clouds; and the graph-filtering module couples the above two modules, refining the coarse reconstruction through a learnt graph topology to obtain the final reconstruction. The proposed decoder leverages a learnable graph topology to push the codeword to preserve representative features and further improve the unsupervised-learning performance. We further provide theoretical analyses of the proposed architecture. We provide an upper bound for the reconstruction loss and further show the superiority of graph smoothness over spatial smoothness as a prior to model 3D point clouds. In the experiments, we validate the proposed networks in three tasks, including 3D point cloud reconstruction, visualization, and transfer classification. The experimental results show that (1) the proposed networks outperform the state-of-the-art methods in various tasks, including reconstruction and transfer classification; (2) a graph topology can be inferred as auxiliary information without specific supervision on graph topology inference; (3) graph filtering refines the reconstruction, leading to better performances; and (4) designing a powerful decoder could improve the unsupervised-learning performance, just like a powerful encoder.

17.
Thorac Cancer ; 10(11): 2096-2105, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499597

RESUMO

BACKGROUND: The current staging systems do not consider the tumor location of thymomas, and its clinical relevance is poorly understood. This study aimed to evaluate the impact of tumor location on the clinicopathological features and prognosis of thymomas. METHODS: We performed a retrospective review of patients at our institution who underwent an extended thymectomy for a thymoma from 1976 to 2015. The tumor location was classified as either the superior or inferior mediastinum based on the maximum tumor diameter. The clinicopathological characteristics of the thymoma were also evaluated. Kaplan-Meier estimates and Cox proportional hazards models were used to analyze the survival outcomes and risk factors for recurrence. RESULTS: A total of 194 patients with thymoma were eligible for this study. Compared with the inferior mediastinum group (n = 167), the superior mediastinum group (n = 27) had a higher frequency of myasthenia gravis (MG), advanced Masaoka-Koga staging, disease progression and recurrence (P < 0.05). The Kaplan-Meier analysis demonstrated thymomas in the superior mediastinum had worse survival outcomes that included overall survival, progression-free survival and disease-free survival (P < 0.05). The multivariate analysis showed tumor location was an independent prognostic factor for all the survival outcomes (P < 0.05). Furthermore, the tumor location (P = 0.004) and Masaoka-Koga stage (P < 0.001) were the only two independent risk factors for recurrence in the multivariate analysis. CONCLUSIONS: The clinicopathological features of thymomas on MG, Masaoka-Koga staging, disease progression, and recurrence were different between locations of superior and inferior mediastinum locations. Thymomas in the superior mediastinum tended to be associated with worse survival and increased recurrence.

18.
Polymers (Basel) ; 11(9)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31492029

RESUMO

Although recent work has shown natural lignin products are promising to fabricate various polymer based functional composites, high-value applications were challenged by their structural complexity and inhomogeneity. This work specially assessed the potential of four technical lignins for cellulose based functional films production. These four technical lignins were obtained by emerging pretreatment systems, i.e., lactic acid-betaine deep eutectic solvent (DES), ethanol organosolv, soda/anthraquinone (Soda/AQ) and the sodium salicylate hydrotrope, and their phenolic substructures were comparatively identified by prevalent 31P NMR technique. The influence of lignin chemical structure on the antioxidant potential and UV-shielding performance of the prepared cellulose/technical lignin composite films were assessed. Results showed severe organosolv and soda/AQ pretreatment produced technical lignins with higher total phenolic hydroxyl groups (3.37 and 3.23 mmol g-1 respectively), which also exhibited higher antioxidant activities. The composite films could effectively block the ultraviolet lights especially for UVB region (ultraviolet B, 280-315 nm) at only 5 wt.% lignin content. The contribution of lignin phenolic substructures to both antioxidant activity and UV-shielding property from high to low was syringyl > guaiacyl > p-hydroxyphenyl phenolic hydroxyl groups. This work provided some useful information that could facilitate upstream lignin extraction or downstream value-added applications.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31548078

RESUMO

OBJECTIVE: Ex vivo lung perfusion (EVLP) is reportedly a useful strategy that permits marginal donor lungs to be evaluated and reconditioned for successful lung transplantation (LTx). This systematic review and meta-analysis was performed to evaluate the outcomes of EVLP conducted for marginal donor lungs. METHODS: We searched PubMed, the Cochrane Library, and Embase to select studies describing the results of LTx following EVLP for marginal donor lungs compared with standard LTx without EVLP. We performed a meta-analysis to examine donor baseline characteristics, recipient baseline characteristics, and postoperative outcomes. RESULTS: Of 1380 studies, 8 studies involving 1191 patients met the inclusion criteria. Compared with the non-EVLP group (ie, standard LTx without EVLP), the EVLP group (ie, EVLP of marginal donors following LTx) had similar donor age and sex and recipient baseline age, sex, body mass index, bridge by ventilator/extracorporeal life support/extracorporeal membrane oxygenation, and rate of double LTx but more abnormal donor lung radiographs (P = .0002), a higher smoking history rate (P = .03), and worse donor arterial oxygen tension/inspired oxygen fraction (P < .00001). However, there were no significant differences in outcomes between the EVLP and non-EVLP groups with respect to the length of postoperative intubation, postoperative extracorporeal life support/extracorporeal membrane oxygenation use, length of intensive care unit stay, length of hospital stay, 72-hour primary graft dysfunction of grade 3, 30-day survival, or 1-year survival (all P values > .05). CONCLUSIONS: Posttransplant outcomes were similar between EVLP-treated LTx and standard LTx without EVLP, although the quality of donor lungs was worse with EVLP-treated LTx.

20.
J Colloid Interface Sci ; 556: 324-334, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31454624

RESUMO

Light absorption and carrier transfer, are two sequential and complementary steps related to photocatalysis performance, whereas the collective integration of these two aspects into graphitic carbon nitride (g-C3N4) photocatalyst through polycondensation optimization have seldom been achieved. Herein, we report on tailoring the crystalline structure of g-C3N4 by avoiding the formation of incompletely reacted N-rich intermediates and selective breaking the hydrogen bonds between the layers of g-C3N4 simultaneously. The obtained layer plane ordered porous carbon nitride (LOP-CN) material shows efficient photocatalytic H2 generation performance. The highest H2 evolution rate achieved is 53.8 µmol under λ ≥ 400 nm light irradiation, which is 7.4 times higher than that of g-C3N4 prepared by convention thermal polycondensation. The substantially boosted photocatalytic activity is mainly ascribed to the efficient charge separation on long-range atomic order layer plane and the extended visible light harvesting ability. This work highlights the importance of crystalline structure tailoring in improving charge separation and light absorption of g-C3N4 photocatalyst for boosting its photocatalytic H2 evolution activity.

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