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1.
Artigo em Inglês | MEDLINE | ID: mdl-31953339

RESUMO

Decomposition of crop residues in soil is mediated by microorganisms whose activities varied with fertilization. The complexity of active microorganisms and their interactions by utilizing residues is impossible to disentangle without isotope applications. Thus, 13C-labeled rice residues were employed and DNA stable-isotope probing (DNA-SIP) combined with high-throughput sequencing was applied to identify microbes active in assimilating residue carbon (C). Manure addition strongly modified microbial community compositions involved in the C flow from rice-residues. Relative abundances of bacterial genus Lysobacter and fungal genus Syncephalis were increased, but that of bacterial genus Streptomyces and fungal genus Trichoderma were decreased in soils receiving mineral fertilizers plus manure (NPKM) compared to soils receiving only mineral fertilizers (NPK). Microbes involved in the flow of residue-C formed more complex network in NPKM than that in NPK soils, because of necessity to decompose more diverse organic compounds. The fungal species (Jugulospora rotula and Emericellopsis terricola in NPK and NPKM soils, respectively) were identified as keystone species in network and may significantly contribute to residue-C decomposition. Most of fungal genera in NPKM soils, especially Chaetomium, Staphylotrichum, Penicillium and Aspergillus, responded faster to residue addition than those in NPK soils. This is connected with the changes in the composition of the rice residue during the degradation and with fungal adaptation (abundance and activity) to continuous manure input. Our findings provide fundamental information about the roles of key microbial groups in residue decomposition and offer important cue on manipulating the soil microbiome for residue utilization and C sequestration in soil.Importance Identifying and understanding the active microbial communities and interactions involved in plant-residue utilization is a key question to elucidate the transformation of soil organic matter (SOM) in agricultural ecosystems. Microbial community composition responds strongly to management, but little is known about specific microbial groups involved in plant-residue utilization and consequently microbial functions under distinct fertilization. We combined DNA stable-isotope (13C) probing and high-throughput sequencing to identify active fungal and bacterial groups degrading residues in soils after 3-year mineral fertilization with and without manure. Manuring changed the active microbial composition and complexified microbial interactions involved in residue-C flow. Most fungal genera, especially Chaetomium, Staphylotrichum, Penicillium and Aspergillus, responded to residue addition faster in soils historically received manure. We generated a valuable "library of microorganisms" involved in plant residue utilization for future targeted research to exploit specific functions of microbial groups in organic matter utilization and C sequestration.

3.
ACS Appl Mater Interfaces ; 12(1): 798-806, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31833352

RESUMO

The creation of solar steam generators with both high energy conversion efficiency and desired salt-resistant performance is essential for practical desalination. Herein, we report for the first time the fabrication of polypyrrole-coated biomass porous foam as efficient solar steam generators. The as-prepared foams possess a low thermal conductivity of 0.022 W M-1 K-1 for alkali-treated corn straw (CSA) and 0.027 W M-1 K-1 for both microwave- and alkali-treated corn straw (CSMA). Based on their high light absorption (95-100%), superhydrophilic wettability, excellent thermal insulation, and unique aligned channels, the foams show excellent energy conversion efficiency of 89.74, 91.08, and 91.54% for the polypyrrole-coated CSA (P-CSA) and 96.8, 97.05, and 98.32% for the polypyrrole coated CSMA (P-CSMA) at light intensities of 1, 2, and 3 kW m-2, respectively. Importantly, thanks to their aligned hierarchical channels, our generators show extraordinary salt-resistant performance, e.g., the energy conversion efficiencies of P-CSA and P-CSMA were measured to be 62.30 and 94.7% in 20 wt % NaCl at 1 kW m-2 irradiation, respectively. Furthermore, no obvious salt accumulation was observed after 30 d of continuous operation at real sunlight irradiation, implying an outstanding long-term stability for practical solar steam generation.

4.
J Phys Chem B ; 124(3): 511-518, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31881156

RESUMO

Electrochemical reduction of CO2 to CO offers a promising strategy for regulating the global carbon cycle and providing feedstock for the chemical industry. Understanding the origin that determines the faradaic efficiency (FE) of reduction of CO2 to CO is critical for developing a highly efficient electrocatalyst. Here, by constructing a single-atom Ni catalyst on nitrogen-doped winged carbon nanofiber (NiSA-NWC), we find that the single-atom Ni catalyst possesses the maximum CO FE of over 95% at -1.6 V vs Ag/AgCl, which is about 30% higher than the standard Ni nanoparticles on the same support. The Tafel analysis reveals that the single-atom Ni catalyst has a preferred reduction of CO2 to CO and a slower rate for the hydrogen evolution reaction. We propose that the domination of singular Ni1+ electronic states and limited hydrogen atom adsorption sites on the single-atom Ni catalyst lead to the observed high FE for CO2 reduction to CO.

5.
Sci Rep ; 9(1): 18549, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31811206

RESUMO

The Cordimax stent has proved non-inferior to the Cypher Select durable polymer sirolimus-eluting stent for the primary endpoint of angiographic in-stent late luminal loss and in-stent mean diameter stenosis at 9 months. The trial was designed to compare the efficacy and safety of the Cordimax stent with the Xience V stent in patients undergoing coronary revascularization. This randomized, multicenter trial enrolled 3697 patients treated with Cordimax stent (2460 patients) and Xience V stent (1237 patients). The primary efficacy endpoint was a target-lesion failure (TLF) at 1 year and the primary safety endpoint was a composite of death or myocardial infarction (MI) at 3 years. 3399 patients (91.9%) completed 3-year follow-up. At 1 year, the primary efficacy endpoint occurred in 86 (3.5%) patients in the Cordimax group versus 40 (3.2%) patients in the Xience V group (0.3% absolute risk difference, 95% CI -1.0-1.5%, Pnon-inferiority < 0.0001). At 3 years, the primary safety endpoint occurred in 39 (1.6%) patients in the Cordimax group versus 19 (1.5%) patients in the Xience V group (0.05% absolute risk difference, 95% CI -0.8-0.9%, Pnon-inferiority < 0.0001). The incidence of target lesion revascularization was low in Cordimax group compared with Xience V group (3.6% versus 5.1%, P = 0.03). There were no differences between Cordimax and Xience V in terms of Cardiac death (0.3% versus 0.4%, P = 0.70), myocardial infarction (1.2% versus 0.9%, P = 0.37), and the stent thrombosis (0.4% versus 0.6%, P = 0.61). In conclusion, safety and efficacy outcomes of Cordimax stent were non-inferior to the Xience V stent 3 years after stent implantation.

6.
Molecules ; 24(21)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683678

RESUMO

The enantioselective transformations of indoles preferentially take place in the more-reactive azole ring. However, the methods for the enantioselective functionalization of the indole benzene ring are scarce. In this paper, a series of bifunctional (thio)urea derivatives were used to organocatalyze the enantioselective Friedel-Crafts hydroxyalkylation of indoles with isatins. The resulting products were obtained in good yields (65-90%) with up to 94% enantiomer excess (ee). The catalyst type and the substrate scope were broadened in this methodology.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31659805

RESUMO

OBJECTIVES: The aim of this study is to improve local-drug delivery efficiency and tissue absorption using the ultrasound (US)-responsible drug coating based on a newly developed US-controlled paclitaxel release balloon. BACKGROUND: Low availability of the drug coating remains a major concern of the current drug coated balloon (DCB). The goal of this study is to develop a method to use an US-responsible paclitaxel-loaded microcapsules (PM) as the main content of balloon drug coating to enhance bioavailability of DCB. METHODS: An US-controlled paclitaxel release balloon is designed and fabricated based on the US-responsible paclitaxel-loaded poly (lactic-co-glycolic acid) (PLGA) microcapsules. Rapid exchange percutaneous transluminal coronary angioplasty (PTCA) balloon catheters were coated with the PM. The deployment processes of the paclitaxel-loaded microcapsules coated balloons (PMCB) under US, PMCB without US and a homogenous matrix of paclitaxel and iopromide coated balloon (PICB) were then placed in healthy and stent implanted porcine coronary arteries. RESULTS: In vitro release assay demonstrated an ability of US (1 MHz, 1.22 W/cm2 , 1 minute) to affect the release kinetics of paclitaxel from PM by inducing a 76 ± 5.4% increase in the rate of release. The paclitaxel content in target vessels are 203 ± 37 µg/g for PMCB under US, 85 ± 23 µg/g for PMCB without US, and 107 ± 31 µg/g for PICB 1-hr post-surgery. The availability of the drug for the PMCB reaches 27% under US. CONCLUSIONS: The US-controlled paclitaxel release balloon significantly improved the drug content of the target vessels in the porcine model.

9.
Appl Environ Microbiol ; 85(24)2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31604771

RESUMO

Many Gram-negative bacteria employ N-acylhomoserine lactones (AHLs) as quorum-sensing (QS) signal molecules to regulate virulence expression in a density-dependent manner. Quorum quenching (QQ) via enzymatic inactivation of AHLs is a promising strategy to reduce bacterial infections and drug resistance. Herein, a thermostable AHL lactonase (AidB), which could degrade different AHLs, with or without a substitution of carbonyl or hydroxyl at the C-3 position, was identified from the soil bacterium Bosea sp. strain F3-2. Ultrahigh-performance liquid chromatography analysis demonstrated that AidB is an AHL lactonase that hydrolyzes the ester bond of the homoserine lactone (HSL) ring. AidB was thermostable in the range 30 to 80°C and showed maximum activity after preincubation at 60°C for 30 min. The optimum temperature of AidB was 60°C, and the enzyme could be stably stored in double-distilled water (ddH2O) at 4°C or room temperature. AidB homologs were found only in Rhizobiales and Rhodospirillales of the Alphaproteobacteria AidB from Agrobacterium tumefaciens and AidB from Rhizobium multihospitium (with amino acid identities of 50.6% and 52.8% to AidB, respectively) also showed thermostable AHL degradation activity. When introduced into bacteria, plasmid-expressed AidB attenuated pyocyanin production by Pseudomonas aeruginosa PAO1 and the pathogenicity of Pectobacterium carotovorum subsp. carotovorum Z3-3, suggesting that AidB is a potential therapeutic agent by degrading AHLs.IMPORTANCE A quorum-sensing system using AHLs as the signal in many bacterial pathogens is a critical virulence regulator and an attractive target for anti-infective drugs. In this work, we identified a novel AHL lactonase, AidB, from a soil bacterial strain, Bosea sp. F3-2. The expression of aidB reduced the production of AHL signals and QS-dependent virulence factors in Pseudomonas aeruginosa and Pectobacterium carotovorum The homologs of AidB with AHL-degrading activities were found only in several genera belonging to the Alphaproteobacteria Remarkably, AidB is a thermostable enzyme that retained its catalytic activity after treatment at 80°C for 30 min and exhibits reliable storage stability at both 4°C and room temperature. These properties might make it more suitable for practical application.

10.
Biomed Tech (Berl) ; 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31527289

RESUMO

Coronary stents made of zinc (Zn)-0.8 copper (Cu) (in wt%) alloy were developed as biodegradable metal stents (Zn-Cu stents) in this study. The mechanical properties of the Zn-Cu stents and the possible gain effects were characterized by in vitro and in vivo experiments compared with 316L stainless steel stents (316L stents). Young's modulus of the as-extruded Zn-0.8Cu alloy and properties of the stents, including their intrinsic elastic recoil, stent trackability were evaluated compared with 316L stents. In vivo study was also conducted to evaluate restoration of pulsatility of vessel segment implanted stents. Both Zn-Cu stents and 316L stents have good acute lumen gain. By comparison, the advantages of Zn-Cu stents are as follows: (I) Zn-Cu stents have less intrinsic elastic recoil than 316L stents; (II) stent trackability indicates that Zn-Cu stents have a smaller push force when passing through curved blood vessels, which may cause less mechanical stimulation to blood vessels; (III) in vivo study suggests that Zn-Cu stents implantation better facilitates the recovery of vascular pulsatility.

11.
Materials (Basel) ; 12(18)2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31489918

RESUMO

The copper matrix composites were prepared by spark plasma sintering (SPS). The current-carrying friction and wear tests were carried out on a self-made HST-100 high-speed current-carrying friction and wear tester, and the effect of the graphite content on the current-carrying friction and wear properties of the composite material was studied. The results show that with an increase in graphite content, the average friction coefficient and wear rate of the two materials decreased significantly, the fluctuation amplitude of the friction coefficient was also significantly reduced, and the average friction coefficient of copper-coated graphite composite with graphite content of 10 wt.% was 0.100; when the graphite content was the same and more than 5.0 wt.%, the average friction coefficient and wear rate of copper-graphite composites were slightly higher than copper-copper-coated graphite composites; the current-carrying efficiency and current-carrying stability of the copper matrix composite were obviously higher than that of copper material; there was a mechanical wear area and arc erosion area on the wear surface of the composites, with the increase in graphite content, the adherence and the tear of the mechanical wear area weakened, the rolling, plastic deformation increased, and the surface roughness decreased obviously. The surface roughness of the wear surface of copper-copper-coated graphite composites with graphite content of 10 wt.% was 3.17 µm. The forms of arc erosion included melting and splashing, and were mainly distributed in the friction exit area.

12.
Food Funct ; 10(9): 5290-5301, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31475703

RESUMO

High consumption of cooking oils in modern society is believed to be the major cause of cardiovascular disease. The effect of cooking oils depends on their fatty acid composition. Therefore, it is important to blend different types of oils to improve functional properties. In this study we evaluated the effects of a functional blended oil (BO) composed of a high level of oleic acid (OA) (50.93%) and α-linolenic acid (ALA) (5.41%) on cardiovascular health, blood pressure (BP) and body weight (BW) in comparison with lard oil (LO) and peanut oil (PO). Ninety male Wistar rats were divided into three groups and fed for 12 weeks with BO, LO and PO. Each group was divided into low, middle and high fat groups and fed with oil supply ratios of 6.7%, 10.9% and 48.1%, respectively. After the feeding period, the rats were sacrificed, and data were collected and analyzed. Rats treated with BO especially at a high dose (HBO) showed a significantly lower body weight, fat weight, liver weight, fat ratio, food intake and energy intake. BO significantly reduced n-6/n-3 levels in plasma, liver and adipose tissues as well as serum triglycerides (TGs) and low density lipoprotein cholesterol (LDL-C) but contrarily increased high density lipoprotein cholesterol (HDL-C). Furthermore, HBO treatments decreased mRNA expression of lipid anabolism-related genes, lipid inflammatory-related genes, toll-like receptor 4 (TLR4), nuclear factor kappa beta (NF-κB) and monocyte chemoattractant protein (MCP)-1 and increased lipid catabolism-related genes as well as peroxisome proliferator-activated receptor gamma mRNA (PPARγ mRNA). In terms of antioxidant enzymes, BO treatment has increased the activity of catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) by lowering malondialdehyde (MDA) and reactive oxygen species (ROS) in tissues. Moreover, BO supplementation showed a significant lowering effect on the serum levels of C-reactive protein (CRP) and tumor necrosis factor alpha (TNF-α), blood pressure (BP), atherosclerosis index (AI) and heart rate (HR). These findings highlight that the new blend of canola oil, corn oil, olive oil, peanut oil and sunflower oil with a low n-6/n-3 PUFA ratio of 6 : 1 could prevent and control cardiovascular disease (CVD).

13.
Acta Biomater ; 97: 657-670, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31401346

RESUMO

In the present study, a novel biodegradable Zn-0.8Cu coronary artery stent was fabricated and implanted into porcine coronary arteries for up to 24 months. Micro-CT analysis showed that the implanted stent was able to maintain structural integrity after 6 months, while its disintegration occurred after 9 months of implantation. After 24 months of implantation, approximately 28 ±â€¯13 vol% of the stent remained. Optical coherence tomography and histological analysis showed that the endothelialization process could be completed within the first month after implantation, and no inflammation responses or thrombosis formation was observed within 24 months. Cross-section analysis indicated that the subsequent degradation products had been removed in the abluminal direction, guaranteeing that the strut could be replaced by normal tissue without the risk of contaminating the circulatory system, causing neither thrombosis nor inflammation response. The present work demonstrates that the Zn-0.8Cu stent has provided sufficient structural supporting and exhibited an appropriate degradation rate during 24 months of implantation without degradation product accumulation, thrombosis, or inflammation response. The results indicate that the Zn-0.8Cu coronary artery stent is promising for further clinical applications. STATEMENT OF SIGNIFICANCE: Although Zn and its alloys have been considered to be potential candidates of biodegradable metals for vascular stent use, by far, no Zn-based stent with appropriate medical device performance has been reported because of the low mechanical properties of zinc. The present work presents promising results of a Zn-Cu biodegradable vascular stent in porcine coronary arteries. The Zn-Cu stent fabricated in this work demonstrated adequate medical device performance both in vitro and in vivo and degraded at a proper rate without safety problems induced. Furthermore, large animal models have more cardiovascular similarities as humans. Results of this study may provide further information of the Zn-based stents for translational medicine research.

15.
Sci Adv ; 5(8): eaaw8904, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31467976

RESUMO

The recent discovery of ferromagnetism in two-dimensional (2D) van der Waals (vdW) materials holds promises for spintronic devices with exceptional properties. However, to use 2D vdW magnets for building spintronic nanodevices such as magnetic memories, key challenges remain in terms of effectively switching the magnetization from one state to the other electrically. Here, we devise a bilayer structure of Fe3GeTe2/Pt, in which the magnetization of few-layered Fe3GeTe2 can be effectively switched by the spin-orbit torques (SOTs) originated from the current flowing in the Pt layer. The effective magnetic fields corresponding to the SOTs are further quantitatively characterized using harmonic measurements. Our demonstration of the SOT-driven magnetization switching in a 2D vdW magnet could pave the way for implementing low-dimensional materials in the next-generation spintronic applications.

16.
PeerJ ; 7: e7312, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31392093

RESUMO

The transcriptional activation of heat shock proteins (Hsps) by heat shock transcription factors (Hsfs) is presumed to have a pivotal role in plant heat stress (HS) response. Prunus mume is an ornamental woody plant with distinctive features, including rich varieties and colors. In this study, 18 Hsfs and 24 small Hsps (sHsps) were identified in P. mume. Their chromosomal locations, protein domains, conserved motifs, phylogenetic relationships, and exon-intron structures were analyzed and compared with Arabidopsis thaliana Hsfs or sHsps. A total of 18 PmHsf members were classified into three major classes, A, B, and C. A total of 24 PmsHsps were grouped into eight subfamilies (CI to CIII, P, endoplasmic reticulum, M, and CI- or P-related). Quantitative reverse transcription PCR analysis revealed that members of the A2, A7, and A9 groups became the prominent Hsfs after heat shock, suggesting their involvement in a key regulatory role of heat tolerance. Most of the PmsHsp genes were up-regulated upon exposure to HS. Overall, our data contribute to an improved understanding of the complexity of the P. mume Hsf and sHsp gene families, and provide a basis for directing future systematic studies investigating the roles of the Hsf and sHsp gene families.

17.
Medicine (Baltimore) ; 98(28): e16404, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31305451

RESUMO

BACKGROUND: The role of fruit and vegetables (FVs) consumption in decreasing gallstone disease risk remains contradictory. We performed a meta-analysis to analyze this potential correlation, followed by investigation of dose-response relationship of FVs consumption with gallstone disease. MATERIALS AND METHODS: PubMed, Embase, as well as Web of Science were searched to determine all published researches about the connection of FVs consumption with gallstone disease before March 2018. Relative risks (RRs) or odds ratios (ORs) along with corresponding 95% confidence intervals (CIs) was pooled utilizing random effect models, aiming at examining the correlation of FVs consumption with gallstone disease risk. RESULTS: One cross-sectional study, our case-control studies as well as nine cohort studies were enrolled, covering approximately 33,983 patients with gallstone disease and 1,53,3752 participants. In a pooled analysis, vegetables consumption was significantly related to a decreased gallstone disease risk, (RR = 0.83, 95% CI, 0.74-0.94, I = 91.1%), and for fruits consumption, RR was similar (RR = 0.88, 95%CI, 0.83-0.92, I = 0.01%). This inverse correlation of FVs consumption with gallstone disease risk was solid in most subgroup analysis. The nonlinear dose-response correlation indicated that gallstone risk was reduced by 4% (RR = 0.96, 95%CI, 0.93-0.98) and 3% (RR = 0.97, 95%CI, 0.96-0.98) for every 200 g per day increment in vegetables consumption (P = .001) and fruits consumption (P = .001), respectively. CONCLUSION: This study suggests vegetables and fruits consumption is correlated with a significantly reduced risk of gallstone disease.


Assuntos
Dieta , Frutas , Cálculos Biliares/epidemiologia , Verduras , Cálculos Biliares/prevenção & controle , Humanos
18.
Am J Phys Med Rehabil ; 98(8): e102-e103, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31318761
20.
ACS Appl Mater Interfaces ; 11(30): 27358-27362, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31305992

RESUMO

We report a strong effect of the MXene flake size and surface termination on the dielectric permittivity of MXene polymer composites. Specifically, poly(vinylidene fluoride-trifluoro-ethylene-chlorofluoroehylene) or P(VDF-TrFE-CFE) polymer embedded with large (ca. 4.5 µm) Ti3C2Tx flakes achieves a dielectric permittivity as high as 105 near the percolation limit of 15.3 wt % MXene loading. In comparison, the dielectric permittivity of MXene/P(VDF-TrFE-CFE) using small (ca. 1.5 µm) Ti3C2Tx flakes (S-MXene) achieves a dielectric permittivity of 104 near the percolation limit of 16.8 wt %. Meanwhile, increasing the concentration of surface functional groups on the MXene surface (-O, -F, and -OH) by extending the etching time gives a dielectric constant of 2204 near the percolation limit of 15.7 wt %. The ratio of permittivity to the loss factor of our large flake composite is superior to that of the small flake composite, and to all previously reported carbon-based fillers in P(VDF-TrFE-CFE). We show that the dielectric permittivity enhancement is strongly related to the charge accumulation at the surfaces between the two dimensional (2D) MXene flakes and the polymer matrix under an external applied electric field.

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