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1.
Nanotechnology ; 34(50)2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37789673

RESUMEN

The practical application of Molybdenum sulphide (MoS2) electrodes has been hindered by its structural instability, and poor electrical conductivity. To enhance the cycle stability and rate performance of MoS2in lithium/sodium-ion batteries (LIBs/SIBs), we synthesized a graphene-supported MoS2composite (MoS2@rGO) with affluent covalent bridged bonds through a facile and scalable hydrothermal and annealing process. The covalent bridged bonds of Mo-S-C, Mo-O-C and C-O-S provide an effective charge transfer path between MoS2and graphene, facilitating fast charge hopping and improving rate performance. As anode materials for LIBs, the MoS2@rGO exhibited exceptional long-term cycle life (906 mAh g-1at 1.0 A g-1after 400 cycles) and outstanding rate capability (1267.7/314.7 mAh g-1at 0.1/6.5 A g-1). Additionally, the MoS2@rGO electrode demonstrated a stable reversible capacity of 521.7 mAh g-1at 1.0 A g-1after 700 cycles and excellent rate capabilities of 665.1 and 326.3 mAh g-1at 0.1 and 10.0 A g-1in SIBs. The edge Mo of MoS2is directly coupled with the oxygen of the functional group on rGO, achieved by adjusting the pH value of the solution to tune the surface charge feature, can effectively enhance the structural stability of electrode even under higher current density.

2.
Molecules ; 27(4)2022 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35209018

RESUMEN

The solubility of dehydroabietic acid in (-)-α-pinene, p-cymene, (-)-ß-caryophyllene, (-)-α-pinene + p-cymene, (-)-ß-caryophyllene + p-cymene and (-)-α-pinene + (-)-ß-caryophyllene were determined using the laser monitoring method at atmospheric pressure. The solubility of dehydroabietic acid was positively correlated with temperature from 295.15 to 339.46 K. (-)-α-pinene, p-cymene, and (-)-ß-caryophyllene were found to be suitable for the solubilization of dehydroabietic acid. In addition, the non-random two liquid (NRTL), universal quasi-chemical (UNIQUAC), modified Apelblat, modified Wilson, modified Wilson-van't Hoff, and λh models were applied to correlate the determined solubility data. The modified Apelblat model gave the minor deviation for dehydroabietic acid in monosolvents, while the λh equation showed the best result in the binary solvents. A comparative analysis of compatibility between solutes and solvents was carried out using Hansen solubility parameters. The thermodynamic functions of ΔsolH0, ΔsolS0, ΔsolG0 were calculated according to the van't Hoff equation, indicating that the dissolution was an entropy-driven heat absorption process. The Conductor-like Screening Model for Real Solvents (COSMO-RS) combined with an experimental value was applied to predict the reasonable solubility data of dehydroabietic acid in the selected solvents systems. The interaction energy of the dehydroabietic acid with the solvent was analyzed by COSMO-RS.

3.
Arch Virol ; 161(8): 2117-32, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27169600

RESUMEN

There were three epidemic waves of human infection with avian influenza A (H7N9) virus in 2013-2014. While many analyses of the genomic origin, evolution, and molecular characteristics of the influenza A (H7N9) virus have been performed using sequences from the first epidemic wave, genomic characterization of the virus from the second epidemic wave has been comparatively less reported. In this study, an in-depth analysis was performed with respect to the genomic characteristics of 11 H7N9 virus strains isolated from confirmed cases and four H7N9 virus strains isolated from environmental samples in Shenzhen during the second epidemic wave. Phylogenetic analysis demonstrated that six internal segments of the influenza A (H7N9) virus isolated from confirmed cases and environmental samples in Shenzhen were clustered into two different clades and that the origin of the influenza A (H7N9) virus isolated from confirmed cases in Shenzhen was different from that of viruses isolated during the first wave. In addition, H9N2 viruses, which were prevalent in southern China, played an important role in the reassortment of the influenza A (H7N9) virus isolated in Shenzhen. HA-R47K and -T122A, PB2-V139I, PB1-I397M, and NS1-T216P were the signature amino acids of the influenza A (H7N9) virus isolated from confirmed cases in Shenzhen. We found that the HA, NA, M, and PA genes of the A(H7N9) viruses underwent positive selection in the human population. Therefore, enhanced surveillance should be carried out to determine the origin and mode of transmission of the novel influenza A (H7N9) virus and to facilitate the formulation of effective policies for prevention and containment of a human infection epidemics.


Asunto(s)
Subtipo H7N9 del Virus de la Influenza A/genética , Subtipo H7N9 del Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/virología , Gripe Humana/virología , Enfermedades de las Aves de Corral/virología , Animales , Pollos , China/epidemiología , Genoma Viral , Genómica , Humanos , Subtipo H7N9 del Virus de la Influenza A/clasificación , Gripe Aviar/epidemiología , Gripe Humana/epidemiología , Filogenia , Enfermedades de las Aves de Corral/epidemiología , Proteínas Virales/genética
4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 48(9): 819-22, 2014 Sep.
Artículo en Zh | MEDLINE | ID: mdl-25492296

RESUMEN

OBJECTIVE: To establish the single genome amplification (SGA) method and analyze the quasispecies in HIV-infected patients. METHODS: All 6 sample RNA acquired in 2010 in Shenzhen and genetic sequenced as overlap peaks were extracted and diluted to a single copy, nest-PCR after one step RT-PCR was employed to amplify HIV-1 genome, and then PCR products was purified and sequenced. Mega 4.02 software was used to analyze the genetic distance among HIV-1 quasispecies, and phylogenetic tree was constructed. RESULTS: Our data showed that viral sequences derived from different patients were grouped into different clusters. Subcluster was also observed in several clusters, indicating these existed competition and preferential replication of certain viral strains. The genetic distance within one cluster of 6 samples were between 0.008 and 0.06, it was likely to associate with the duration since infection and viral load. CONCLUSION: SGA is a useful approach to gain information on quasispecies, the genetic distance within one cluster may help to determine the infection time and immune escaping. The analysis of related affecting factors need more samples.


Asunto(s)
Genoma Viral , Infecciones por VIH , Reacción en Cadena de la Polimerasa , Secuencia de Bases , VIH-1 , Humanos , Filogenia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Carga Viral
5.
Nanoscale ; 16(11): 5546-5550, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38440800

RESUMEN

We report the synthesis of nanoporous Cu/Ag bimetallic triangular nanoprisms (BTNPs) using a galvanic replacement method. Based on ultraviolet-visible spectroscopy (UV-vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), X-ray diffraction (XRD), energy dispersive spectrometry (EDS), selected area electron diffraction (SAED) and X-ray photoelectron spectroscopy (XPS) analyses, the structure of Cu/Ag BTNPs was characterized. The prepared Cu/Ag BTNPs exhibited excellent catalytic activity and good cycling stability for the reduction of 4-nitrophenol (4-NP) due to the synergistic effect between Cu and Ag elements. The kinetic rate constant (k) and turnover frequency (TOF) values reached 331 × 10-3 s-1 and 500 × 10-3 s-1, respectively, which were higher than those of previously reported Cu, Ag, Au, Cu/Ag or Cu/Au-based catalysts. We hope that the development of promising routes for high-quality BTNPs can broaden their applications in catalysis and environmental sustainability.

6.
Trials ; 24(1): 732, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37964365

RESUMEN

BACKGROUND: Disrupted sleep is believed to contribute to short- and long-term neurodevelopmental problems in very preterm infants (VPIs). This study presents a protocol for an evaluator-blinded, randomized crossover trial. It aims to assess the sleep efficiency of hospitalized VPIs by providing multisensory stimulation bundles. Furthermore, it aims to observe the intervention impacts on sleep during hospitalization of the VPIs and their sleep and neurodevelopmental outcomes during the first year of post-discharge follow-up. METHODS: The study will be conducted in the neonatology department of a tertiary pediatric teaching hospital. All the eligible VPIs will undergo two types of care in random order: "standard care" (2 weeks) and "standard care plus multisensory stimulation bundles," each lasting 2 weeks. A generated list of random numbers will be used for case sequence allocation. Sleep outcomes will be evaluated using the Actiwatch-2 Actigraph. Moreover, the amplitude-integrated electroencephalography and the Griffiths Mental Development Scales will be used to measure the neurodevelopmental outcomes during hospitalization and in the first year of follow-up of the VPIs. DISCUSSION: The intervention protocol of this study differs from that of other traditional interventions by producing precise and consistent supportive stimulations, similar to maternal tactile, auditory, posture, and visual effects for hospitalized VPIs. This protocol could be an effective measure to facilitate sleep and early neurodevelopment of VPIs. The expected outcomes will help confirm the implementation and generalization of the multisensory stimulation bundles' care protocol in neonatology departments. We expect that the study will positively impact hospitalized VPIs, especially in their sleep and early neurodevelopmental outcomes. It will also provide a new perspective regarding parent and infant interaction strategies, particularly for newborn intensive care units that limit visits because of the global spread of COVID-19. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR 2200059099. Registered on 25 April 2022, https://www.chictr.org.cn/showproj.html?proj=166980 ; the Hospital Research Ethics Committee (approval number: SCMCIRB-K2021086-1, Version 01), approved on 21 January 2022.


Asunto(s)
Cuidados Posteriores , Recien Nacido Prematuro , Lactante , Recién Nacido , Humanos , Niño , Estudios Cruzados , Alta del Paciente , Sueño , Ensayos Clínicos Controlados Aleatorios como Asunto
7.
Front Microbiol ; 14: 1191059, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37303792

RESUMEN

Introduction: The continuous application of cow manure in soil for many years leads to the accumulation of heavy metals, pathogenic microorganisms, and antibiotic resistance genes. Therefore, in recent years, cow manure has often been mixed with botanical oil meal as organic fertilizer applied to farmland to improve soil and crop quality. However, the effects of various botanical oil meal and cow manure mixed organic fertilizers on soil microbial composition, community structure, and function, tobacco yield, and quality remain unclear. Methods: Therefore, we prepared organic manure via solid fermentation by mixing cow manure with different oil meals (soybean meal, rape meal, peanut bran, sesame meal). Then, we studied its effects on soil microbial community structure and function, physicochemical properties, enzyme activities, tobacco yield and quality; then we analyzed the correlations between these factors. Results and discussion: Compared with cow manure alone, the four kinds of mixed botanical oil meal and cow manure improved the yield and quality of flue-cured tobacco to different degrees. Peanut bran, which significantly improved the soil available phosphorus, available potassium, and NO3--N, was the best addition. Compared with cow manure alone, soil fungal diversity was significantly decreased when rape meal or peanut bran was combined with cow manure, while soil bacterial and fungal abundance was significantly increased when rape meal was added compared with soybean meal or peanut bran. The addition of different botanical oil meals significantly enriched the subgroup_7 and Spingomonas bacteria and Chaetomium and Penicillium fungi in the soil. The relative abundances of functional genes of xenobiotics biodegradation and metabolism, soil endophytic fungi, and wood saprotroph functional groups increased. In addition, alkaline phosphatase had the greatest effect on soil microorganisms, while NO3--N had the least effect on soil microorganisms. In conclusion, the mixed application of cow manure and botanical oil meal increased the available phosphorus and potassium contents in soil; enriched beneficial microorganisms; promoted the metabolic function of soil microorganisms; increased the yield and quality of tobacco; and improved the soil microecology.

8.
ACS Omega ; 6(17): 11650-11659, 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-34056320

RESUMEN

Nickel and tungsten, combined with copper, were incorporated into a magnesium aluminum spinel to form a multifunctional catalyst (Ni-W-Cu/MgAl2O4). Characterization results suggested that the adjacent Cu not only facilitated the reduction of W6+ to W5+ with substantial oxygen vacancies but also promoted the reducibility of the Ni species. Besides, the incorporation of Ni, W, and Cu into the support enhanced the catalytic acidity, as well as the L acid sites. The catalyst exhibited a strong synergistic effect between the three metals and the support, resulting in higher catalytic activity for the one-pot hydrogenolysis of cellulose to ethylene glycol. High cellulose conversion (100%) and ethylene glycol yield (52.8%) were obtained, even under a low H2 pressure of 3 MPa.

9.
J Colloid Interface Sci ; 511: 119-127, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29017097

RESUMEN

A facile template-free Ostwald ripening method is developed for the preparation of the reduced graphene oxide supported splode-like NiCo2O4 hollow microsphere (SNHM/rGO). The graphene oxide used in the reaction mixture is found to play a crucial role in the formation of the SNHM/rGO. It promotes the formation of the NiCo-glycerol microspheres suitable for the Ostwald ripening to form the reduced graphene oxide supported hollow NiCo-glycerol microspheres, which is important for the subsequent calcination to form the SNHM/rGO. The obtained SNHM/rGO shows a great promise as the anode for lithium-ion batteries and can deliver a stable reversible capacity of 1048.1 mA h g-1 at the current density of 100 mA g-1. The performance of the SNHM/rGO is much higher than that of most NiCo2O4-based materials reported previously, strongly suggesting that the SNHM/rGO could be used as the anode for practical applications. This is well supported by the higher performance of the LiCoO2//SNHM-rGO full cell. The excellent electrochemical performance can be attributed to the specific structure of the SNHM/rGO, which comprises the splode-like hollow NiCo2O4 microspheres with the reduced graphene oxide integrated.

10.
PLoS One ; 12(5): e0177514, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28542182

RESUMEN

OBJECTIVES: Varicella (chickenpox) is a highly transmissible childhood disease. Between 2010 and 2015, it displayed two epidemic waves annually among school populations in Shenzhen, China. However, their transmission dynamics remain unclear and there is no school-based vaccination programme in Shenzhen to-date. In this study, we developed a mathematical model to compare a school-based vaccination intervention scenario with a baseline (i.e. no intervention) scenario. METHODS: Data on varicella reported cases were downloaded from the Infectious Disease Reporting Information Management System. We obtained the population size, age structure of children aged 15 or under, the class and school distribution from Shenzhen Education Bureau. We developed an Agent-Based Susceptible-Exposed-Infectious-Recovered (ABM-SEIR) Model that considered within-class, class-to-class and out-of-school transmission modes. The intervention scenario was that school-wide vaccination intervention occurred when an outbreak threshold was reached within a school. We varied this threshold level from five to ten cases. We compared the reduction of disease outbreak size and estimated the key epidemiological parameters under the intervention strategy. RESULTS: Our ABM-SEIR model provided a good model fit to the two annual varicella epidemic waves from 2013 to 2015. The transmission dynamics displayed strong seasonality. Our results suggested that a school-based vaccination strategy could effectively prevent large outbreaks at different thresholds. CONCLUSIONS: There was a considerable increase in reported varicella cases from 2013 to 2015 in Shenzhen. Our modelling study provided important theoretical support for disease control decision making during school outbreaks and the development of a school-based vaccination programme.


Asunto(s)
Varicela/prevención & control , Varicela/transmisión , Modelos Estadísticos , Instituciones Académicas/estadística & datos numéricos , Adolescente , Varicela/epidemiología , Niño , Preescolar , China/epidemiología , Brotes de Enfermedades/prevención & control , Femenino , Humanos , Lactante , Recién Nacido , Masculino
11.
Mar Pollut Bull ; 84(1-2): 263-7, 2014 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-24856092

RESUMEN

A sorbent for oil spill cleanup was prepared through a novel strategy by treating polyurethane sponges with silica sol and gasoline successively. The oil sorption capacity, oil/water selectivity, reusability and sorption mechanism of prepared sorbent were studied. The results showed that the prepared sorbent exhibited high sorption capacity and excellent oil/water selectivity. 1g of the prepared sorbent could adsorb more than 100 g of motor oil, while it only picks up less than 0.1 g of water from an oil-water interface under both static and dynamic conditions. More than 70% of the sorption capacity remained after 15 successive sorption-squeezing cycles, which suggests an extraordinary high reusability. The prepared sorbent is a better alternative of the commercial polypropylene sorbent which are being used nowadays.


Asunto(s)
Contaminación por Petróleo , Petróleo/análisis , Polipropilenos , Poliuretanos , Purificación del Agua/métodos , Agua/química , Adsorción , Contaminantes Químicos del Agua
12.
Zhonghua Liu Xing Bing Xue Za Zhi ; 31(8): 913-5, 2010 Aug.
Artículo en Zh | MEDLINE | ID: mdl-21162995

RESUMEN

OBJECTIVE: To understand the rule of vpr gene variance of HIV-1 strains. METHODS: RT-PCR was used to amplify vpr gene of HIV-1 strains in Shenzhen. PCR products were sequenced and used for gene phylogenetic analysis and the 32 - 46 amino acids of Vpr protein were compared. The difference of 77 amino acid polymorphism distribution between domestic region and foreign region was analyzed. RESULTS: 01_AE was the major HIV-1 subtype in Shenzhen. The gene distance among subtype B was larger than in other subtypes. 77-amino acid of Vpr protein had three polymorphism forms as Arginin, Glutamine and Histidine, with Glutamine as the wild form. There were no significant differences in the three amino acid distributions between HIV-1 strains from domestic region and foreign region. CONCLUSION: vpr genes of different HIV-1 strains belonged to 01_AE subtype. There was polymorphism seen in the vpr gene which was consistent with both domestic and international HIV-1 strains.


Asunto(s)
Genes prv , VIH-1 , Infecciones por VIH/epidemiología , VIH-1/genética , Epidemiología Molecular , Filogenia
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