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1.
Molecules ; 28(9)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37175360

RESUMO

Carbon sequestration is the primary function of biochar. Hence, it is necessary to design biochar with high carbon (C) retention and low C loss. In this study, three P compounds, including KH2PO4, Ca(H2PO4)2, and NH4H2PO4, were premixed with corn stalk (1:4, w/w), aiming to produce biochars (CSB+K, CSB+Ca, and CSB+N) with high C sequestration and slow release of P at three temperatures (300, 500, and 700 °C). The addition of all P sources obviously increased C retention, with the order of NH4H2PO4 (65.6-83.5%) > Ca(H2PO4)2 (60.4-78.2%) > KH2PO4 (50.1-76.1%), compared with the pristine biochar (47.8-73.6%). The addition of Ca(H2PO4)2 and KH2PO4 led to an increase in aromaticity and graphitization, as evidenced by H/C, FTIR, Raman and XPS analysis, whereas an opposite result occurred on CSB+N. Furthermore, all three phosphates reduced C loss of biochars with H2O2 oxidation, and CSB+Ca showed the best effect. Ca(H2PO4)2 and KH2PO4 pretreated biochars had higher resistance to K2Cr2O7 oxidation and thermal treatment. In contrast, the C loss of NH4H2PO4-added biochar at 500 and 700 °C with K2Cr2O7 oxidation was increased by 54% and 36%, respectively. During the pyrolysis process, Ca(H2PO4)2 was transformed into insoluble Ca2P2O7, leading to the lowest P release rate of CSB+Ca. This study indicates that co-pyrolysis of corn stalk and Ca(H2PO4)2 is optimal for increasing C retention, enhancing C stability and improving slow-release performance of P regardless of pyrolysis temperature.


Assuntos
Fosfatos , Fósforo , Temperatura , Sequestro de Carbono , Pirólise , Peróxido de Hidrogênio , Carvão Vegetal , Carbono
2.
Entropy (Basel) ; 25(11)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37998204

RESUMO

Compute-and-Forward (CoF) is an innovative physical layer network coding strategy, designed to enable receivers in wireless communications to effectively utilize interference. The key idea of CoF is to implement integer combinations based on the codewords from multiple transmitters, rather than decoding individual source codewords. Although CoF is widely used in wireless relay networks, there are still some problems to be solved, such as rank failure, single antenna reception, and the shortest vector problem. In this paper, we introduce a successive extended CoF (SECoF) as a pioneering solution tailored for multi-source, multi-relay, and multi-antenna wireless relay networks. First, we analyze the traditional CoF, and design a SECoF method combining the concepts of matrix projection and successive interference cancellation, which overcomes the problem of CoF rate tending to zero and rank failure and improves the network performance. Secondly, we obtain an approximate solution to the integer-value coefficient vectors by using the LLL lattice-based resolution algorithm. In addition, we deduce the corresponding concise formulas of SECoF. Simulation results show that the SECoF has strong robustness and the approaches outperform the state-of-the-art methods in terms of computation rate, rank failure probability, and outage probability.

3.
Sensors (Basel) ; 22(16)2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-36016051

RESUMO

The electromagnetic (EM) scattering characteristics of the rough sea surface is very important for target surveying and detection in a sea environment. This work proposes a scaled sea surface designing method based on a rough thin-film medium. For the prototype sea surface, the permittivity is calculated with the seawater temperature, salinity, and EM wave frequency according to the Debye model. The scale film material is mixed with carbon black and epoxy, whose volume ratio is optimized with the genetic algorithm through the existing electromagnetic parameter library. This method can overcome the previous difficulties of adjusting the same permittivity of the prototype sea water. According to the EM scaled theory, the scaled geometric sample is numerically generated with the D-V spectrum for the given wind speed, and is fabricated using 3D printing to keep the similar seawater shape. Then, the sample is sprayed with a layer of film material for EM scattering measurement. The simulated and measured radar cross-section (RCS) results show good consistency for the prototype seawater and scaled materials, which indicates the proposed scaled method is a more efficient method to get the seawater scattering characteristics.

4.
Nano Lett ; 21(15): 6711-6717, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34297585

RESUMO

Despite the great appeal of two-dimensional semiconductors for electronics and optoelectronics, to achieve the required charge carrier concentrations by means of chemical doping remains a challenge due to large defect ionization energies (IEs). Here, by decomposing the defect IEs into three parts based on ionization process, we propose a conceptual picture that the large defect IEs are caused by two effects of reduced dimensionality. While the quantum confinement effect makes the neutral single-electron point defect levels deep, the reduced screening effect leads to high energy cost for the electronic relaxation. The first-principles calculations for black phosphorus and MoS2 do demonstrate the general trend. Using BP monolayer either embedded into dielectric continuum or encapsulated between two hBN layers, we demonstrate the feasibility of increasing the screening to reduce the defect IEs. Our analysis is expected to help achieve effective carrier doping and open ways toward more extensive applications of 2D semiconductors.

5.
Molecules ; 27(15)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35956817

RESUMO

It is inevitable that reclaimed cotton stalks will contain a certain amount of plastic film due to the wide application of plastic mulching during the process of cotton cultivation, and this makes it inappropriate to return it to the field or for it to be processed into silage. In this study, biochars were prepared by the co-pyrolysis of cotton stalk with low-density polyethylene (LDPE) in the proportions of 1:0, 3:1, 2:1, and 1:1 (w/w) at 400 °C, 450 °C, and 500 °C and maintaining them for 1 h. The effects of the co-pyrolysis of cotton stalk with LDPE on the properties of biochars (e.g., pH, yield, elemental analysis, specific surface area, etc.) and the Pb(II) removal capacity were analyzed. Co-pyrolysis cotton stalks with LDPE could delay the decomposition of LDPE but could promote the decomposition of cotton stalk. At 400 °C and 450 °C, the addition of LDPE decreased the H/C ratio, while no significant difference was found between the pristine biochar and the blended biochar pyrolyzed at 500 °C. An FTIR analysis indicated that the surface functional groups of biochar were not affected by the addition of LDPE, except for CH3 and CH2. The results of the SEM showed that LDPE could cover the surface of biochar when pyrolyzed at 400 °C, while many macropores were found in the blended biochar that was pyrolyzed at 450 °C and 500 °C, thus increasing its surface area. The blended biochar that was pyrolyzed at 500 °C was more effective in the removal of Pb(II) than the cotton-stalk-derived biochar, which was dominated by monolayer adsorption with a maximum adsorption capacity of approximately 200 mg·g-1. These results suggested that the co-pyrolysis of cotton stalks and LDPE may be used to produce biochar, which is a cost-effective adsorbent for heavy metal removal from aqueous solutions.


Assuntos
Polietileno , Pirólise , Adsorção , Carvão Vegetal/química , Chumbo
6.
Entropy (Basel) ; 24(6)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35741496

RESUMO

Recently, deep neural network-based image compressed sensing methods have achieved impressive success in reconstruction quality. However, these methods (1) have limitations in sampling pattern and (2) usually have the disadvantage of high computational complexity. To this end, a fast multi-scale generative adversarial network (FMSGAN) is implemented in this paper. Specifically, (1) an effective multi-scale sampling structure is proposed. It contains four different kernels with varying sizes so that decompose, and sample images effectively, which is capable of capturing different levels of spatial features at multiple scales. (2) An efficient lightweight multi-scale residual structure for deep image reconstruction is proposed to balance receptive field size and computational complexity. The key idea is to apply smaller convolution kernel sizes in the multi-scale residual structure to reduce the number of operations while maintaining the receptive field. Meanwhile, the channel attention structure is employed for enriching useful information. Moreover, perceptual loss is combined with MSE loss and adversarial loss as the optimization function to recover a finer image. Numerous experiments show that our FMSGAN achieves state-of-the-art image reconstruction quality with low computational complexity.

7.
Sensors (Basel) ; 20(18)2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32942579

RESUMO

In the skeleton-based human action recognition domain, the spatial-temporal graph convolution networks (ST-GCNs) have made great progress recently. However, they use only one fixed temporal convolution kernel, which is not enough to extract the temporal cues comprehensively. Moreover, simply connecting the spatial graph convolution layer (GCL) and the temporal GCL in series is not the optimal solution. To this end, we propose a novel enhanced spatial and extended temporal graph convolutional network (EE-GCN) in this paper. Three convolution kernels with different sizes are chosen to extract the discriminative temporal features from shorter to longer terms. The corresponding GCLs are then concatenated by a powerful yet efficient one-shot aggregation (OSA) + effective squeeze-excitation (eSE) structure. The OSA module aggregates the features from each layer once to the output, and the eSE module explores the interdependency between the channels of the output. Besides, we propose a new connection paradigm to enhance the spatial features, which expand the serial connection to a combination of serial and parallel connections by adding a spatial GCL in parallel with the temporal GCLs. The proposed method is evaluated on three large scale datasets, and the experimental results show that the performance of our method exceeds previous state-of-the-art methods.


Assuntos
Algoritmos , Movimento , Redes Neurais de Computação , Esqueleto/fisiologia , Humanos
8.
Nano Lett ; 19(12): 8343-8356, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31659907

RESUMO

Anisotropic hydrogels with a hierarchical structure can mimic biological tissues, such as neurons or muscles that show directional functions, which are important factors for signal transduction and cell guidance. Here, we report a mussel-inspired approach to fabricate an anisotropic hydrogel based on a conductive ferrofluid. First, polydopamine (PDA) was used to mediate the formation of PDA-chelated carbon nanotube-Fe3O4 (PFeCNT) nanohybrids and also used as a dispersion medium to stabilize the nanohybrids to form a conductive ferrofluid. The ferrofluid can respond to an orientated magnetic field and be programed to form aligned structures, which were then frozen in a hydrogel network formed via in situ free-radical polymerization and gelation. The resulted hydrogel shows directional conductive and mechanical properties, mimicking an oriented biological tissue. Under external electrical stimulation, the orientated PFeCNT nanohybrids can be sensed by the myoblasts cultured on the hydrogel, resulting in the oriented growth of cells. In summary, the mussel-inspired anisotropic hydrogel with its aligned structural complexity and anisotropic properties together with the cell affinity and tissue adhesiveness is a potent multifunctional biomaterial for mimicking oriented tissues to guide cell proliferation and tissue regeneration.


Assuntos
Bivalves , Óxido Ferroso-Férrico , Hidrogéis , Campos Magnéticos , Mioblastos/metabolismo , Nanocompostos/química , Animais , Anisotropia , Linhagem Celular , Condutividade Elétrica , Óxido Ferroso-Férrico/química , Óxido Ferroso-Férrico/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Camundongos , Mioblastos/citologia
9.
Water Sci Technol ; 81(10): 2270-2280, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32701504

RESUMO

It is of great significance to remove Cr(VI) from water as a result of its high toxicity. Biochar from corn straw was modified by different acids (HNO3, H2SO4 and H3PO4) to remove Cr(VI) from aqueous solution. To estimate the removal mechanisms of Cr(VI) by the acid-modified biochars, batch experiments were performed in the light of contact time, Cr(VI) concentration, and pH, and the characteristics of acid-modified biochars before and after Cr(VI) adsorption were investigated by Fourier transform infrared spectra (FTIR) and X-ray photoelectron spectroscopy (XPS). The adsorption kinetics of Cr(VI) by acid-modified biochars were consistent with the pseudo-second-order model, and the adsorption isotherm obeyed the Freundlich model. Furthermore, the acid- modified biochars could supply more oxygen-containing functional groups (-COOH and -OH) as electron donor (e-) and hydrogen ion (H+) to enhance the reduction of Cr(VI) to Cr(III), resulting in enhanced removal of Cr(VI). HNO3-modified biochar exhibited the highest removal efficiency of Cr(VI). In general, the acid modifition of biochar was an effective method to increase the removal of Cr(VI).


Assuntos
Poluentes Químicos da Água/análise , Zea mays , Adsorção , Carvão Vegetal , Cromo/análise , Concentração de Íons de Hidrogênio , Cinética
10.
J Environ Sci Health B ; 55(11): 941-950, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32715911

RESUMO

Animal manures usually contain high contents of heavy metals (HMs) and thus pose a considerable threat to human health and environment when applied to soil. In this study, the effect of pyrolysis temperature (300 °C, 400 °C, 500 °C, 600 °C, and 700 °C) on the properties of biochar produced from chicken manure was studied. In addition, the response of speciation, bioavailability, leachability, and environmental risk of HMs in biochar to different pyrolysis temperature was investigated. The results showed that biochars pyrolyzed at high temperatures generally had high pH, ash content, surface area, and stability. As the pyrolysis temperature increased, the total concentrations of Cu, Zn, Cr, and Ni continually increased, whereas those of Pb and Cd initially increased and then decreased. Moreover, the transformation of the bioavailable fractions of HMs into stable fractions obviously increased with increasing pyrolysis temperature. Thus, pyrolysis at high temperature led to a further decrease in the bioavailability, leachability, and environmental risk of six HMs, as shown by DTPA, TCLP, and the potential ecological risk index. Overall, it is convincing that that 700 °C is the optimal temperature when considering the quality and environmental safety of biochar derived from chicken manure.


Assuntos
Carvão Vegetal/química , Esterco , Metais Pesados/química , Gerenciamento de Resíduos/métodos , Animais , Disponibilidade Biológica , Galinhas , Temperatura Alta , Metais Pesados/análise , Metais Pesados/farmacocinética , Pirólise , Fatores de Risco , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética , Espectroscopia de Infravermelho com Transformada de Fourier
11.
J Med Virol ; 91(3): 337-346, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30133872

RESUMO

Hemorrhagic fever with renal syndrome (HFRS) is highly endemic in China, where approximately 90% of the total human cases in the world are reported. The Hebei province, one of areas with the highest prevalence, has reported HFRS cases every year in the last two decades. This study describes the spatiotemporal patterns of HFRS in the Hebei province from 2001 to 2016, detects the high-risk spatiotemporal clusters of HFRS, and provides valuable information for planning and implementation of local preventive measures. For the purpose of the analysis, HFRS cases recorded during the sixteen years in the Hebei province were aggregated into three temporal periods (2001-2006, 2007-2012, and 2013-2016). Spatiotemporal analyses, including Global spatial autocorrelation analysis and Kulldorff's scan statistical analysis, were applied to analyze te spatiotemporal clusters of HFRS at the county level. The results revealed that the spatial extent of the HFRS epidemic in the Hebei province changed dynamically from 2001 to 2016, which indicated that a comprehensive preventative strategy should be implemented in the northeastern regions of the Hebei province in spring.


Assuntos
Febre Hemorrágica com Síndrome Renal/epidemiologia , Análise Espaço-Temporal , China/epidemiologia , Análise por Conglomerados , Sistemas de Informação Geográfica , Humanos , Incidência , Estações do Ano
12.
BMC Infect Dis ; 19(1): 765, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477045

RESUMO

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) is an emerging zoonotic infectious disease caused by hantaviruses which circulate worldwide. So far, it was still considered as one of serious public health problems in China. The present study aimed to reveal the stabilities and variations of hantavirus infection in Hebei province located in North China through a long-term retrospective observation. METHODS: The epidemiological data of HFRS cases from all 11 cities of Hebei province since 1981 through 2016 were collected and descriptively analyzed. The rodent densities, species compositions and virus-carrying rates of different regions were collected from six separated rodent surveillance points which set up since 2007. The molecular diversity and phylogenetic relationship of hantaviruses circulating among rodents were analyzed based on partial viral glycoprotein gene. RESULTS: HFRS cases have been reported every year in Hebei province, since the first local case was identified in 1981. The epidemic history can be artificially divided into three phases and a total of 55,507 HFRS cases with 374 deaths were reported during 1981-2016. The gender and occupational factors of susceptible population were invarible throughout, however age of that was gradually aging. The annual outbreak peak always present in spring, while the main epidemic region had gradully altered from south to northeast. Surveillance of rodents revealed that residential rodents significantly possessed higher density and virus-carring rate than field rodents. The house rat, Rattus norvegicus, was the dominant rodent species and Seoul virus S3 sub-genotype which is continued but slightly evolving perhaps to be the sole pathogen for local HFRS cases of Hebei province. CONCLUSIONS: This long-term province-wide surveillance and epidemiological analysis has revealed the stabilities and variations of hantavirus infection in North China. In order to improve current prevention and control strategies of HFRS in China, all surveillance should be continuously enhanced and variations should be paid more attentions.


Assuntos
Infecções por Hantavirus/epidemiologia , Febre Hemorrágica com Síndrome Renal/epidemiologia , Animais , China/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Epidemias/estatística & dados numéricos , Genótipo , Orthohantavírus/classificação , Orthohantavírus/genética , Orthohantavírus/isolamento & purificação , Infecções por Hantavirus/virologia , Febre Hemorrágica com Síndrome Renal/virologia , Humanos , Filogenia , Dinâmica Populacional , Vigilância da População , Ratos , Estudos Retrospectivos , Roedores/virologia , Fatores de Tempo , Zoonoses/epidemiologia , Zoonoses/virologia
13.
Entropy (Basel) ; 21(5)2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-33267203

RESUMO

The rolling bearings often suffer from compound fault in practice. Compared with single fault, compound fault contains multiple fault features that are coupled together and make it difficult to detect and extract all fault features by traditional methods such as Hilbert envelope demodulation, wavelet transform and empirical node decomposition (EMD). In order to realize the compound fault diagnosis of rolling bearings and improve the diagnostic accuracy, we developed negentropy spectrum decomposition (NSD), which is based on fast empirical wavelet transform (FEWT) and spectral negentropy, with cyclic extraction as the extraction method. The infogram is constructed by FEWT combined with spectral negentropy to select the best band center and bandwidth for band-pass filtering. The filtered signal is used as a new measured signal, and the fast empirical wavelet transform combined with spectral negentropy is used to filter the new measured signal again. This operation is repeated to achieve cyclic extraction, until the signal no longer contains obvious fault features. After obtaining the envelope of all extracted components, compound fault diagnosis of rolling bearings can be realized. The analysis of the simulation signal and the experimental signal shows that the method can realize the compound fault diagnosis of rolling bearings, which verifies the feasibility and effectiveness of the method. The method proposed in this paper can detect and extract all the fault features of compound fault completely, and it is more reliable for the diagnosis of compound fault. Therefore, the method has practical significance in rolling bearing compound fault diagnosis.

14.
Entropy (Basel) ; 20(7)2018 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-33265600

RESUMO

Aiming to solve the problem of accurate diagnosis of the size and location of rolling bearing faults, a novel quantitative and localization fault diagnosis method of the rolling bearing is proposed based on the quantitative mapping model (QMM). The fault size and location of the rolling bearing affect the impulse type and the modulation degree of the vibration signal, which subsequently changes the complexity and randomness of the time-domain distribution of the vibration signal. According to the relationship between the multiscale permutation entropy (MPE) of the vibration signal and rolling bearing fault size, an average MPE (A-MPE) index is proposed to establish linear and nonlinear QMMs through the regression function. The proper QMM is selected through the error rate of fault size prediction to achieve a quantitative fault diagnosis of the rolling bearing. Due to the mathematical characteristics of the QMM, the localization fault diagnosis is realized. The multiscale morphological filtering (MMF) method is also introduced to extract the time-domain geometric feature of the fault bearing vibration signal and to improve the QMM accuracy of the fault size prediction. The results show that the QMM has a great effect on the quantitative fault size prediction and localization diagnosis of the rolling bearing.

15.
J Surg Res ; 215: 190-195, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28688646

RESUMO

BACKGROUND: Laparoscopy-assisted gastrectomy (LAG) has already been introduced for advanced gastric cancer (AGC). However, little is known as to whether LAG is also applicable for AGC with serous invasion given the possibility that malignant cell dissemination and local recurrence incidence might increase. This study was designed to evaluate the technical feasibility and oncological adequacy of LAG in comparison with open gastrectomy (OG) for AGC with serous invasion. METHODS: A retrospective case-matched study was conducted to compare LAG and OG for AGC with serous invasion. For this study, 67 consecutive patients with AGC who underwent LAG between April 2007 and March 2011 were recruited and compared with 67 AGC patients who received OG during the same time period. We analyzed the patient demographics, operative results, pathologic characteristics, and long-term outcomes. RESULTS: No significant differences were observed in the numbers of harvested lymph nodes (24.0 ± 8.2 versus 25.6 ± 8.8, P = 0.083) or the average distance between the proximal and distal resection margins (4.8 ± 2.5 cm versus 4.6 ± 2.4 cm, P = 0.354; 6.6 ± 4.2 cm versus 7.6 ± 4.7 cm, P = 0.105) in the LAG and OG groups. The complication rate was similar between the LAG and OG groups (6.0% versus 4.5%, P = 0.500). The duration of postoperative analgesic use was significantly shorter in the LAG group than in the OG group (2.9 ± 0.6 d versus 3.9 ± 0.6 d, P < 0.001). The 5-y cumulative survival and recurrence-free survival rates of the two groups were similar (31.3% versus 29.9%, P = 0.949; 29.9% versus 23.9%, P = 0.716). CONCLUSIONS: The findings in this study suggest that LAG is a feasible and safe procedure for patients with seriously invasive AGC and predict acceptable long-term oncologic outcomes. LAG may be an appropriate choice to treat patients with seriously invasive AGC.


Assuntos
Adenocarcinoma/cirurgia , Gastrectomia/métodos , Laparoscopia , Neoplasias Gástricas/cirurgia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Invasividade Neoplásica , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Análise de Sobrevida , Resultado do Tratamento
16.
Ecotoxicol Environ Saf ; 142: 250-256, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28427033

RESUMO

A pot experiment was carried out to investigate the single and combined effect of different concentrations of sulfadiazine (SDZ) (1 and 10mgkg-1) and copper (Cu) (20 and 200mgkg-1) stresses on growth, hydrogen peroxide (H2O2), malondialdehyde (MDA), antioxidant enzyme activities of wheat seedlings and their accumulation. High SDZ or Cu level significantly inhibited the growth of wheat seedlings, but the emergence rate was only inhibited by high SDZ level. The presence of Cu reduced the accumulation of SDZ, whereas the effect of SDZ on the accumulation of Cu depended on their concentrations. Low Cu level significantly increased the chlorophyll content, while high Cu level or both SDZ concentrations resulted in a significant decrease in the chlorophyll content as compared to the control. Additionally, H2O2 and MDA contents increased with the elevated SDZ or Cu level. The activities of superoxide dismutase, peroxidase and catalase were also stimulated by SDZ or Cu except for the aerial part treated by low Cu level and root treated by high SDZ level. The joint toxicity data showed that the toxicity of SDZ to wheat seedlings was generally alleviated by the presence of Cu, whereas the combined toxicity of SDZ and Cu was larger than equivalent Cu alone.


Assuntos
Cobre/toxicidade , Plântula/efeitos dos fármacos , Poluentes do Solo/toxicidade , Sulfadiazina/toxicidade , Triticum/efeitos dos fármacos , Catalase/metabolismo , Clorofila/metabolismo , Interações Medicamentosas , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Oxirredução , Peroxidase/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Superóxido Dismutase/metabolismo , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
17.
Ecotoxicol Environ Saf ; 134P1: 43-52, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27584823

RESUMO

Elevated concentrations of heavy metals and antibiotics often coexist in agricultural soils due to land application of large amounts of animal manure. The experiment was conducted to investigate the single and joint effects of different concentrations of sulfadiazine (SDZ) (10mgkg-1 and 100mgkg-1) and copper (Cu) (20mgkg-1 and 200mgkg-1) on soil microbial activity, i.e. fluorescein diacetate (FDA) hydrolysis, dehydrogenase (DHA) and basal respiration (BR), microbial biomass and community structure estimated using phospholipid fatty acids (PLFA), and community level physiological profiles (CLPP) using MicroResp™. High concentration of SDZ or Cu significantly reduced microbial activity during the whole incubation period, while the inhibiting effect of low concentration of SDZ or Cu was only visible within 14 days of incubation. The total PLFA concentration was reduced by SDZ and/or Cu, which resulted from reduced bacterial and actinomycetic biomass. The addition of SDZ and/or Cu decreased the bacteria:fungi ratio, whereas only the addition of high Cu concentration significantly decreased Gram+:Gram- ratio. The addition of Cu obviously inhibited the dissipation of SDZ, which could affect the combined effects of both on microbial activity, biomass and community structure. Principal component analysis of the CLPP and PLFA data clearly revealed the notable effects of SDZ and/or Cu on soil microbial community structure.

18.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(4): 425-9, 2016 Apr.
Artigo em Zh | MEDLINE | ID: mdl-27323613

RESUMO

OBJECTIVE: To analyze the effect of Chinese herbs used by Prof. LI Tao on peripheral blood T subsets in treating multiple sclerosis (MS) by using association rules and statistical methods, thereby providing evidence for optimizing prescriptions. METHODS: Data of MS inpatients and outpatients recorded by data collecting system, Xiyuan Hospital, China Academy of Chinese Medical Sciences were resorted. The relationship between Chinese herbs and T cell subsets were analyzed using SPSS17.0 and Aprior module in SPSS Clementine 12.0. RESULTS: Radix bupleuri, Radix Paeoniae alba, Fructus Aurantii, Atractylodes, and Radix Glycyrrhizae were most commonly used herbal combinations.Radix Aconiti lateralis preparata and Rhizoma Smilacis glabrae were often added. Radix Aconiti lateralis preparata was associated with decreased Th1 cells (confidence level 83.78%, supportive level 36.26%). Decreased Th1 cell was associated with Radix Aconiti lateralis preparata (confidence level 71.26%, supportive level 36.26%).Radix Aconiti lateralis preparata was obviously associated with decreased Th1 cells. Radix Bupleuri, Radix Paeoniae alba, bitter orange, Atractylodes , Radix glycyrrhizae, and Radix Aconiti lateralis preparata could reduce peripheral blood Th1 subsets of MS patients and elevate Th2 subsets (all P < 0.01). CONCLUSIONS: The herbal combination of Radix Bupleuri, Radix Paeoniae alba, Fructus Aurantii, Atractylodes, Radix Glycyrrhizae, Rhizoma Smilacis glabrae, and Radix Aconiti lateralis preparata could lower peripheral blood Th1 cells and elevate Th2 cells, and prevent the relapse of MS possibly by reducing Th1 cells and elevating Th2 cells. Especially Radix Aconiti lateralis preparata played important roles in aforesaid changes of Th1 and Th2.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Esclerose Múltipla/terapia , Subpopulações de Linfócitos T/efeitos dos fármacos , Aconitum/química , Atractylodes/química , Bupleurum/química , China , Frutas/química , Glycyrrhiza/química , Humanos , Paeonia/química , Raízes de Plantas/química , Rizoma/química , Smilacaceae/química
19.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(7): 842-848, 2016 07.
Artigo em Zh | MEDLINE | ID: mdl-30634213

RESUMO

OBJECTIVE: To observe the effect and underlying mechanism of Chinese herbal com- pound (CHC) for supplementing qi and activating blood circulation (SQABC) combined with dual antiplatelet drugs (DA) on oxidized low density lipoprotein (ox-LDL) induced human umbilical vein endothelial cell (HUVEC) injury and platelet adhesion evoked by injured endothelial cells (ECs) based on P13K/Akt signaling pathway. METHODS: HUVECs were randomly divided into 5 groups, i.e., the blank control group, the model group (80 mg/L ox-LDL) , the DA group (15 µg/mL aspirin +10 µg/ mL clopidogrel +80 mg/L ox-LDL) , the Panax Quinquefolium saponins ( PQS, 160 µLg/mL) + Panax Notoginseng saponins (PNS, 160 µg/mL) +DA group, the LY294002 (30 µg/mL) + PQS + PNS + DA group. HUVEC apoptosis rate and platelet adhesion to HUVECs were detected by flow cytometry. Concentration of lactate dehydrogenase ( LDH) in HUVEC supernatant was detected by biochemical assay. Concentration of intercellular adhesion molecular ([CAM) was detected by radioimmunoassay. Protein expressions of p-P13K and p-Akt in HU- VECs were detected by Western blot. RESULTS: Compared with the blank control group, the apoptosis rate of HUVECs, mean fluorescence indicator ( MFI) , concentrations of both LDH and ICAM increased (P <0. 05) , and p-Akt protein expression decreased (P <0. 05) in the model group. Compared with the model group, the apoptosis rate of HUVECs and LDH concentration increased (P <0. 05), concentrations of MFI and ICAM obviously decreased (P <0. 05) in the DA group. The apoptosis rate, MFI, concentrations of both LDH and ICAM all decreased in the PQS + PNS + DA group (P <0. 05). p-Akt protein. expres- sion in HUVECs obviously increased in the PQS + PNS + DA group (P <0. 05). Compared with the DA group, HUVEC apoptosis rate, MFI, concentrations of both LDH and ICAM in supernatant obviously decreased, p-Akt expression in HUVECs increased in the PQS + PNS + DA group (all P <0. 05). p-Akt protein expression in HUVECs was inhibited after adding specific P13K inhibitor LY294002. Protection men- tioned above all disappeared in the PQS + PNS + DA group (P <0. 05). CONCLUSION: CHC for SQABC combined with DA could alleviate ox-LDL induced apoptosis of endothelial cells and reduce injured ECs e- voked platelet adhesion via up-regulation of P13K/Akt pathway in ECs.


Assuntos
Células Endoteliais da Veia Umbilical Humana , Inibidores da Agregação Plaquetária , Qi , Apoptose , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Lipoproteínas LDL , Masculino , Inibidores da Agregação Plaquetária/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Regulação para Cima
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(12): 3505-9, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-26964239

RESUMO

Based on a long-term experiment in Shenyang Experimental Station, the effect of manure application on the contents and budgets of Cu, Zn and Cd in the arable soil was studied. The experiment included four treatments: no mature addition (CK), mature addition 10 t · ha⁻¹ year⁻¹(M1), 25 t · ha⁻¹ year⁻¹ (M2), and 50 t · ha⁻¹ year⁻¹(M3). The result showed that Cu, Zn and Cd in soil were accumulated with manure application and prolongation of experiment, and the accumulative magnitude increased with increasing of manure application. The average annual growth rates of the heavy metals in the four treatments (CK, M1, M2, M3) were 2.83%, 6.56%, 7.54%, 8.96%; 0.03%, 3.44%, 4.53%, 6.64% and 1.51%, 8.01%, 10. 27%, 16. 08% for Cu, Zn and Cd, respectively. After six years of the experiment, the content of Cd in the M3 treatment was quite close to the threshold of Chinese Soil Quality Standard Grade III (1 mg · kg⁻¹, GB15618-1995). After 12 years of the experiment, the contents of Cu in the mature-amended treatments fell in the Chinese Soil Quality Standard Grade III, which should be paid more attention. Although the heavy metals in soil were gradually accumulated, the Cu, Zn and Cd levels in crop grain were still below the National Food Contamination Standards (GB2762-2005; GB13106-91; GB15199-94), indicating the contents of heavy metals in crop produced from contaminated soil might not exceed the corresponding standards. The contents of Cu, Zn and Cd in the straw were much greater than those in the grain. The removal of heavy metal by crop was in the order of M3 > M2 > M1 > CK. The average amounts of Cu, Zn and Cd annually removed from the soil in the four treatments (CK, M1, M2 and M3) were 35.68, 47.80, 63.65, 69.64; 249.14, 375.22, 375.16, 444.44, and 0.83, 1.39, 1.64, 1.66 g · ha⁻¹, respectively. The contents of heavy metals in organic manure varied in different years: the contents of Cu and Zn increased year by year, while Cd presented a decreasing trend. The average amounts of Cu, Zn and Cd annually remained in the soil in the treatments M1, M2 and M3 were 2 283.0, 5 763.7, 11585.4; 2 483.3, 6 771.4, 13 849.2 and 4.8, 13.9, 29.5 g · ha⁻¹, respectively. Since the heavy metals in organic manure markedly fluctuated in different years, the average residuals can only reflect the changing trend. Therefore, the residuals of heavy metals in the soil could be accurately predicted only according to status of manure in a given year.

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