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1.
Risk Manag Healthc Policy ; 14: 4073-4081, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616194

RESUMO

Background: Despite a flood of research on job satisfaction, few studies have examined how and why social support influences job satisfaction. This study aimed to explore how social support has an indirect effect on job satisfaction by examining its impact on emotional exhaustion and anxiety symptoms among residents of the physicians standardized residency training program in China. Methods: This cross-sectional study adopted questionnaires to collect data from residents in the standardized residency training program in China. The PROCESS macro for SPSS based on ordinary least-squares regression and the bootstrap method was used. The indirect effect of social support was examined using bootstrapping procedures. A serial multiple mediation model was examined in which social support was associated with job satisfaction via emotional exhaustion and anxiety symptoms. Results: There were 269 residents who provided usable data for the analysis. The mean age of residents was 25.98 years old. Close to half (52%) of the participants were female. The total indirect effect of social support on job satisfaction was significant (ab=0.21, SE=0.05, CI=0.12 to 0.32). The specific indirect effect 1 (social support→emotional exhaustion→job satisfaction) was significant (a1b1=0.12, SE=0.04, CI=0.05 to 0.19). The specific indirect effect 2 (social support→anxiety symptoms→job satisfaction) was significant (a2b2=0.07, SE=0.03, CI=0.02 to 0.13).The specific indirect effect 3 (social support→emotional exhaustion→anxiety symptoms→job satisfaction) was also found to be significant through both optimism and work engagement (a1a3b2=0.03, SE=0.01, CI=0.01 to 0.05). Conclusion: It seems critical for hospital management to develop a supportive work environment to improve the effects of emotional exhaustion and anxiety symptoms and to provide sufficient support to improve job satisfaction among residents in standardized residency training programs.

2.
Fitoterapia ; 156: 105070, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34718093

RESUMO

Kiwi (Actinidia chinensis) plants are severely destroyed by canker disease which is caused by the bacterium Pseudomonas syringae pv. actinidiae (Psa). This program tries to find anti-Psa agents among secondary metabolites of endophytic fungi from kiwi plant itself. The chemical investigation on one kiwi endophytic fungi, Fusarium tricinctum, resulted in the isolation of nine new imidazole alkaloids, fusaritricines A-I (1-9) together with seven known analogues (10-16). The structures of new compounds were established by extensive spectroscopic methods. Compounds 2, 3, 9, and 13 showed good antibacterial activity against Psa with MIC values between 25 and 50 µg/mL. It is suggested that imidazole alkaloids should be potential anti-Psa agents.

3.
BMC Psychiatry ; 21(1): 460, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34548045

RESUMO

BACKGROUND: Although studies indicate that social support is related to emotional exhaustion, depression symptoms, and anxiety symptoms, the underlying mechanism between those variables remains unknown. METHODS: Based on a sample of 254 residents in standardized residency training programs, two mediation models were tested in which emotional exhaustion served as a mediator in the relationship between social support and anxiety symptoms/depression symptoms. We used the following self-reported questionnaires as instruments to collect data: zung self-rating depression scale, zung self-rating anxiety scale, social support rating scale, and emotional exhaustion scale. RESULTS: In the final study sample, the mean age of the residents was 25.92 years old (SD =1.88), and a total of 41.3% were male, and 58.7% were female. This current study suggested that social support was proven to be a relevant factor affecting anxiety symptoms and depression symptoms. Particularly, the results also indicated that emotional exhaustion partially mediated the impact of social support on anxiety symptoms and depression symptoms among Chinese residents in the standardized residency training program. CONCLUSIONS: Our study signifies that enhancements in social support and reduction of emotional exhaustion can directly or indirectly affect anxiety symptoms and depression symptoms among Chinese residents in the standardized residency training program. These findings will offer insight for health-sector managers to develop programs aimed at social support and adopt individual-level interventions and organization-level interventions to reduce emotional exhaustion.


Assuntos
Depressão , Internato e Residência , Adulto , Ansiedade/diagnóstico , Depressão/diagnóstico , Emoções , Feminino , Humanos , Masculino , Apoio Social , Inquéritos e Questionários
4.
Front Microbiol ; 11: 590451, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33362737

RESUMO

Tomato spotted wilt orthotospovirus (TSWV) causes serious crop losses worldwide and is transmitted by Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). NSs protein is the silencing suppressor of TSWV and plays an important role in virus infection, cycling, and transmission process. In this research, we investigated the influences of NSs protein on the interaction of TSWV, plants, and F. occidentalis with the transgenic Arabidopsis thaliana. Compared with the wild-type Col-0 plant, F. occidentalis showed an increased number and induced feeding behavior on transgenic Arabidopsis thaliana expressing exogenous NSs. Further analysis showed that NSs reduced the expression of terpenoids synthesis-related genes and the content of monoterpene volatiles in Arabidopsis. These monoterpene volatiles played a repellent role in respect to F. occidentalis. In addition, the expression level of plant immune-related genes and the content of the plant resistance hormone jasmonic acid (JA) in transgenic Arabidopsis were reduced. The silencing suppressor of TSWV NSs alters the emission of plant volatiles and reduces the JA-regulated plant defenses, resulting in enhanced attractiveness of plants to F. occidentalis and may increase the transmission probability of TSWV.

5.
J Cell Mol Med ; 24(24): 14231-14246, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33128346

RESUMO

Acute coronary syndrome caused by the rupture of atherosclerotic plaques is one of the primary causes of cerebrovascular and cardiovascular events. Neovascularization within the plaque is closely associated with its stability. Long non-coding RNA (lncRNA) serves a crucial role in regulating vascular endothelial cells (VECs) proliferation and angiogenesis. In this study, we identified lncRNA HCG11, which is highly expressed in patients with vulnerable plaque compared with stable plaque. Then, functional experiments showed that HCG11 reversed high glucose-induced vascular endothelial injury through increased cell proliferation and tube formation. Meanwhile, vascular-related RNA-binding protein QKI5 was greatly activated. Luciferase reporter assays and RNA-binding protein immunoprecipitation (RIP) assays verified interaction between them. Interestingly, HCG11 can also positively regulated by QKI5. Bioinformatics analysis and luciferase reporter assays showed HCG11 can worked as a competing endogenous RNA by sponging miR-26b-5p, and QKI5 was speculated as the target of miR-26b-5p. Taken together, our findings revered that the feedback loop of lncRNA HCG11/miR-26b-5p/QKI-5 played a vital role in the physiological function of HUVECs, and this also provide a potential target for therapeutic strategies of As.


Assuntos
Regulação da Expressão Gênica , Glucose/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , MicroRNAs/genética , Neovascularização Fisiológica/genética , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/genética , Idoso , Biomarcadores , Linhagem Celular Tumoral , Células Cultivadas , Feminino , Genes Reporter , Glucose/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Interferência de RNA
6.
Comput Biol Med ; 126: 104048, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33068809

RESUMO

BACKGROUND: In recent years, numerous fusion algorithms have been proposed for multimodal medical images. The Laplacian pyramid is one type of multiscale fusion method. Although the pyramid-based fusion algorithm can fuse images well, it has the disadvantages of edge degradation, detail loss and image smoothing as the number of decomposition layers increase, which is harmful for medical diagnosis and analysis. METHOD: This paper proposes a medical image fusion algorithm based on the Laplacian pyramid and convolutional neural network reconstruction with local gradient energy strategy, which can greatly improve the edge quality. First, multimodal medical images are reconstructed through convolutional neural network. Then, the Laplacian pyramid is applied in the decomposition and fusion process. The optimal number of decomposition layers is determined by experiments. In addition, a local gradient energy fusion strategy is utilized to fuse the coefficients in each layer. Finally, the fused image is output through Laplacian inverse transformation. RESULTS: Compared with existing algorithms, our fusion results represent better vision quality performance. Furthermore, our algorithm is considerably superior to the compared algorithms in objective indicators. In addition, in our fusion results of Alzheimer and Glioma, the disease details are much clearer than those of compared algorithms, which can provide a reliable basis for doctors to analyze disease and make pathological diagnoses.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Algoritmos
7.
ACS Omega ; 5(34): 21961-21967, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32905428

RESUMO

To comprehensively understand the chemical constituents of the edible mushroom Agrocybe salicacola and their biological functions, a phytochemical separation of the cultural broth of A. salicacola led to the isolation of four new illudane sesquiterpenoids, agrocybins H-K (1-4), along with 10 known analogues (5-14). Compounds 2-4 were racemates of which 2 and 3 were further separated into single enantiomers as 2a/2b and 3a/3b. All new structures with absolute configurations were elucidated on the basis of an extensive spectroscopic analysis and quantum chemistry calculations. Compound 1 possesses a new carbon skeleton that might be derived from the protoilludane backbone. Compounds 1, 5, 8, and 9 show a certain degree of cytotoxicity to five human cancer cell lines. Compound 1 shows a mild inhibitory effect on nitric oxide production with an IC50 value of 31.4 µM. It is concluded that A. salicacola is rich in illudin derivatives with potential bioactivity prospects, which would make A. salicacola a good material of medicine and food homology.

8.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(7): 711-715, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32669166

RESUMO

OBJECTIVE: To study the value of fractional anisotropy (FA) of regions of interest (ROI) on magnetic resonance diffusion tensor imaging (DTI) in bilirubin-induced neurological dysfunction in neonates. METHODS: A total of 91 neonates with hyperbilirubinemia who were hospitalized from January 2017 to January 2018 were enrolled. According to the peak level of total serum bilirubin, they were divided into three groups: mild/moderate increase (n=45), severe increase (n=35), and extremely severe increase (n=11). According to the presence or absence of abnormal neurological manifestations, they were divided into two groups: neurological dysfunction (n=20) and non-neurological dysfunction (n=71). Ten healthy full-term infants were enrolled as the control group. Head DTI was performed for all neonates to measure the FA values of the bilateral globus pallidus, the anterior limb of the internal capsule, the posterior limb of the internal capsule, and the cerebellar dentate nucleus. RESULTS: The extremely severe increase group had significantly lower FA values of the globus pallidus than the control, mild/moderate increase, and severe increase groups (P<0.05). The severe increase group had significantly lower FA values of the globus pallidus than the control group (P<0.05). The extremely severe increase group had significantly lower FA values of the posterior limb of the internal capsule than the control, mild/moderate increase, and severe increase groups (P<0.05). The neurological dysfunction group had significantly lower FA values of the globus pallidus and the posterior limb of the internal capsule than the non-neurological dysfunction group (P<0.05). CONCLUSIONS: Serum bilirubin level combined with the changes in the DTI FA values of the globus pallidus and the posterior limb of the internal capsule can be used to predict the injury of cerebral nuclei and white matter fibers.


Assuntos
Imagem de Tensor de Difusão , Substância Branca , Anisotropia , Bilirrubina , Encéfalo , Imagem de Difusão por Ressonância Magnética , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
9.
Comput Methods Programs Biomed ; 196: 105603, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32570007

RESUMO

Two-scale image representation of base and detail in the spatial-domain is a well-known decomposition scheme for its lower computational complexity than that performed in the transform-domain in the field of image fusion. Unfortunately, for a pseudo-colour input image, the base and detail images in the spatial-domain obtained via image decomposition scheme always display in greyscale. In this paper, a two-scale image fusion method with adaptive threshold obtained by Otsu's method is proposed for pseudo-colour image in the colour space domain. For greyscale image, detail and base image are obtained using structural information extracted from the difference image between a global and a local patch size. Consequently, local edge-preserving filter for preserving luminance information and local energy with the discussed window size are adopted to combine base and detail image. Experimental results show that structural and luminance information has been better preserved in terms of subjective and objective evaluations for medical image and protein image fusion. Specially, a two-step non-parametric statistical test (Friedman test and Nemenyi post-hoc test) with p-values is adopted to analysis the statistical significant of the relative difference between the proposed and compared methods in terms of values of objective metrics including 30 co-registered pairs of imaging data.


Assuntos
Algoritmos
10.
J Nat Prod ; 83(5): 1524-1531, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32315183

RESUMO

Eight previously undescribed sesquiterpenoids, tremutins A-H (1-8), together with three known ones (9-11), were isolated from cultures of the basidiomycetes Irpex lacteus. Structures of the new compounds together with absolute configurations were elucidated on the basis of extensive spectroscopic methods, as well as single-crystal X-ray diffractions and equivalent circulating density calculations. Compounds 1 and 2 possess an unusual 6/7-fused ring system that might be derived from a tremulane framework. Compounds 3-7 and 9-11 are tremulane sesquiterpenoids of which 4 and 5 are the first tremulane examples with a 1,2-epoxy moiety to be reported. Compounds 6, 7, 10, and 11 possess weak activities to several human cancer cell lines. Compound 8 shows a weak inhibitory effect on NO production with a half maximal inhibitory concentration (IC50) value of 22.7 µM. Compound 1 inhibits the lipopolysaccharide (LPS)-induced proliferation of B lymphocyte cells with an IC50 value of 22.4 µM, while 2 inhibits concanavalin A (Con A)-induced T cell proliferation and LPS-induced B lymphocyte cell proliferation with IC50 values of 16.7 and 13.6 µM, respectively.


Assuntos
Polyporales/metabolismo , Sesquiterpenos/química , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Antibióticos Antineoplásicos/biossíntese , Antibióticos Antineoplásicos/farmacologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Fermentação , Humanos , Imunossupressores/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Difração de Raios X
11.
BMC Microbiol ; 20(1): 72, 2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32228456

RESUMO

BACKGROUND: Plant viruses move through plasmodesmata (PD) to infect new cells. To overcome the PD barrier, plant viruses have developed specific protein(s) to guide their genomic RNAs or DNAs to path through the PD. RESULTS: In the present study, we analyzed the function of Pepper vein yellows virus P4 protein. Our bioinformatic analysis using five commonly used algorithms showed that the P4 protein contains an transmembrane domain, encompassing the amino acid residue 117-138. The subcellular localization of P4 protein was found to target PD and form small punctates near walls. The P4 deletion mutant or the substitution mutant constructed by overlap PCR lost their function to produce punctates near the walls inside the fluorescent loci. The P4-YFP fusion was found to move from cell to cell in infiltrated leaves, and P4 could complement Cucumber mosaic virus movement protein deficiency mutant to move between cells. CONCLUSION: Taking together, we consider that the P4 protein is a movement protein of Pepper vein yellows virus.


Assuntos
Biologia Computacional/métodos , Vírus de Plantas/fisiologia , Tabaco/virologia , Proteínas Virais/metabolismo , Algoritmos , Cucumovirus/fisiologia , Mutação , Folhas de Planta/virologia , Plasmodesmos/metabolismo , Plasmodesmos/virologia , Domínios Proteicos , Tabaco/metabolismo , Proteínas Virais/química , Proteínas Virais/genética
12.
IEEE J Biomed Health Inform ; 24(4): 1169-1179, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31352358

RESUMO

The recently developed multiscale-based fusion methods can be improved with two approaches: an advanced image decomposition scheme and an advanced fusion rule. In this paper, three-layer image decomposition, enhanced illumination fusion rule-based method is proposed. The proposed method includes three steps. First, each input image is decomposed into its corresponding smooth, texture, and edge layers using defined local extrema and low-pass filters in the spatial domain. Second, three different strategies are applied as fusion rules for the three-layer representation. To preserve the illumination closely related to tumors, the illumination is corrected by applying a higher contrast to the decomposed image details, including the texture and edge inputs, such as those found in grayscale CT and MRI images. The final fused image is created by the addition of the normalized smooth, texture, and edge image layers. The experiments demonstrate that the proposed method performs better than the existing state-of-the-art fusion methods.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imagem Multimodal/métodos , Encéfalo/diagnóstico por imagem , Lógica Fuzzy , Humanos , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Tomografia Computadorizada por Raios X/métodos
13.
Microb Biotechnol ; 12(6): 1453-1463, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31566880

RESUMO

Although many biocontrol bacteria can be used to improve plant tolerance to stresses and to promote plant growth, the hostile environmental conditions on plant phyllosphere and the limited knowledge on bacterial colonization on plant phyllosphere minimized the beneficial effects produced by the biocontrol bacteria. Rhodopseudomonas palustris strain GJ-22 is known as a phyllosphere biocontrol agent. In this paper, we described detailed processes of strain GJ-22 colony establishment at various colonization stages. Four different types of bacterial colonies, Type 1, scattered single cells; Type 2, small cell clusters; Type 3, small cell aggregates; and Type 4, large cell aggregates, were observed in the course of bacterial colonization. We categorized bacterial colonization into four phases, which were, Phase I: bacterial colony exists as Type 1 and cell population reduced quickly; Phase II: Type 1 evolved into Type 2 and cell population remained steady; Phase III: Type 3 arose and replaced Type 2, and cell population expanded slowly; and Phase IV: Type 3 matured into Type 4 and cell population increased quickly. We have shown that the preferable location sites of bacterial aggregates on leaf phyllosphere are grooves between plant epidermal cells. Analyses of expressions of plant defence-related genes showed that, starting from Phase III, bacterial cells in the Type 3 and Type 4 colonies produced unidentified signals to induce host defence against Tobacco mosaic virus infection. In addition, we determined the crucial role of aggregates formation of GJ-22 cell on plant phyllosphere in terms of bacterial cell stress tolerance and ISR (induced systemic resistance) priming. To our knowledge, this is the first report focused on the colonization process of a phyllosphere biocontrol agent and gave a clear description on the morphological shift of bacterial colony on phyllosphere.


Assuntos
Doenças das Plantas/imunologia , Folhas de Planta/microbiologia , Rodopseudomonas/crescimento & desenvolvimento , Vírus do Mosaico do Tabaco/imunologia , Tabaco/imunologia , Tabaco/microbiologia , Dinâmica Populacional
14.
AMB Express ; 9(1): 141, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506772

RESUMO

Development of a genetic tool for visualization of photosynthetic bacteria (PSB) is essential for understanding microbial function during their interaction with plant and microflora. In this study, Rhodopseudomonas palustris GJ-22-gfp harboring the vector pBBR1-pckAPT-gfp was constructed using an electroporation transformation method and was used for dynamic tracing of bacteria in plants. The results showed that strain GJ-22-gfp was stable and did not affect the biocontrol function, and the Confocal Laser Scanning Microscopy (CLSM) results indicated it could successfully colonised on the surface of leaf and root of tobacco and rice. In tobacco leaves, cells formed aggregates on the mesophyll epidermal cells. While in rice, no aggregate was found. Instead, the fluorescent cells colonise the longitudinal intercellular spaces between epidermal cells. In addition, the results of strain GJ-22 on the growth promotion and disease resistance of tobacco and rice indicated that the different colonization patterns might be related to the bacteria could induce systemic resistance in tobacco.

15.
Mol Plant Pathol ; 20(7): 895-906, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31074170

RESUMO

Sclerotinia sclerotiorum is a devastating necrotrophic fungal pathogen that infects over 400 species of plants worldwide. Reactive oxygen species (ROS) modulations are critical for the pathogenic development of S. sclerotiorum. The fungus applies enzymatic and non-enzymatic antioxidants to cope with the oxidative stress during the infection processes. Survival factor 1 was identified and characterized to promote survival under conditions of oxidative stress in Saccharomyes cerevisiae. In this research, a gene named SsSvf1 was predicted to encode a survival factor 1 homologue in S. sclerotiorum. SsSvf1 transcripts showed high expression levels in hyphae under oxidative stress. Silencing of SsSvf1 resulted in increased sensitivity to oxidative stress in culture and increased levels of intracellular ROS. Transcripts of SsSvf1 showed a dramatic increase during the initial stage of infection and the gene-silenced strains displayed reduced virulence on oilseed rape and Arabidopsis thaliana. Inhibition of plant ROS production partially restores virulence of SsSvf1 gene-silenced strains. SsSvf1 gene-silenced strains exhibited normal oxalate production, but were impaired in compound appressorium formation and cell wall integrity. The results suggest that SsSvf1 is involved in coping with ROS during fungal-host interactions and plays a crucial role in the pathogenicity of S. sclerotiorum.


Assuntos
Ascomicetos/metabolismo , Ascomicetos/patogenicidade , Proteínas Fúngicas/metabolismo , Estresse Oxidativo , Sequência de Aminoácidos , Ascomicetos/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Proteínas Fúngicas/química , Inativação Gênica/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Pressão Osmótica , Estresse Oxidativo/efeitos dos fármacos , Virulência/efeitos dos fármacos , Vitamina K 3/farmacologia
16.
Front Microbiol ; 10: 233, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30837967

RESUMO

Sclerotinia sclerotiorum is a destructive ascomycete plant pathogen with worldwide distribution. Extensive research on different aspects of this pathogen's capability to cause disease will help to uncover clues about new ways to safely control Sclerotinia diseases. The thioredoxin (Trx) system consists of Trx and thioredoxin reductase (TrxR), which play critical roles in maintenance of cellular redox homeostasis. In this study, we functionally characterized a gene encoding a TrxR (SsTrr1) in S. sclerotiorum. The amino acids of SsTrr1 exhibited high similarity with reported TrxRs in plant pathogens and targeted silencing of SsTrr1 lead to a decrease in TrxR activities of mycelium. SsTrr1 showed high expression levels during hyphae growth, and the levels decreased at the different stages of sclerotial development. SsTrr1 gene-silenced strains produced a smaller number of larger sclerotia on potato dextrose agar medium. The observations were consistent with the inhibitory effects on sclerotial development by the TrxR inhibitor, anrunofin. The expression of SsTrr1 showed a dramatic increase under the oxidative stress and the hyphal growth of gene-silenced strains showed more sensitivity to H2O2. SsTrr1 gene-silenced strains also showed impaired virulence in different hosts. Taken together, our results suggest that SsTrr1 encodes a TrxR that is of great important for oxidative stress tolerance, virulence, and sclerotial development of S. sclerotiorum.

17.
Chem Commun (Camb) ; 55(22): 3203-3206, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30801585

RESUMO

Co/Co9S8 nanoparticles encapsulated in a N, S, and O ternary-doped carbon matrix were synthesized utilizing a Co-NSOMOF as a single precursor, and they exhibited excellent bifunctional electrocatalytic activity for the OER and HER. Impressively, the water splitting cell exhibited a low cell voltage of 1.56 V at 10 mA cm-2. The high performances were attributed to the synergistic effect and the protection of multi-heteroatom doped carbon shells for active Co/Co9S8 nanoparticles.

18.
Sheng Wu Gong Cheng Xue Bao ; 35(2): 244-253, 2019 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-30806054

RESUMO

Natural lignocellulosic materials contain cellulose, hemicellulose, and lignin. Cellulose hydrolysis to glucose requires a series of lignocellulases. Recently, the research on the synergistic effect of lignocellulases has become a new research focus. Here, four lignocellulase genes encoding ß-glucosidase, endo-1,4-ß-glucanase, xylanase and laccase from termite and their endosymbionts were cloned into pETDuet-1 and pRSFDuet-1 and expressed in Escherichia coli. After SDS-PAGE analysis, the corresponding protein bands consistent with the theoretical values were observed and all the proteins showed enzyme activities. We used phosphoric acid swollen cellulose (PASC) as substrate to measure the synergistic effect of crude extracts of co-expressing enzymes and the mixture of single enzyme. The co-expressed enzymes increased the degradation efficiency of PASC by 44% compared with the single enzyme mixture; while the degradation rate increased by 34% and 20%, respectively when using filter paper and corn cob pretreated with phosphoric acid as substrates. The degradation efficiency of the co-expressed enzymes was higher than the total efficiency of the single enzyme mixture.


Assuntos
Isópteros , Animais , Celulase , Celulose , Hidrólise , Lignina , Simbiose , beta-Glucosidase
19.
IEEE Trans Biomed Eng ; 66(4): 1172-1183, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30207947

RESUMO

Detail information on objects of interest plays a vital role in current medical diagnosis. However, the existing multimodal sensor fusion methods cause problems of low contrast and color distortion during the process of integration. Therefore, the preservation of detail information in high contrast is worthy of investment in the field of medical image fusion. This paper presents a new multiscale fusion-based framework using the local Laplacian pyramid transform (LLP) and adaptive cloud model (ACM). The proposed framework, LLP+ACM, includes three key modules. First, the input images are decomposed into detail-enhanced approximate and residual images using LLP. Second, ACM is adopted to fuse the approximate images. A salience match tool is used to fuse the residual images. Third, the fused image is reconstructed using the inversed LLP. Experiments show that the proposed LLP+ACM significantly improves detail information with high contrast and reduces the color distortion of the fused images in both subjective and objective evaluations.


Assuntos
Computação em Nuvem , Interpretação de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/métodos , Análise de Ondaletas , Algoritmos , Encéfalo/diagnóstico por imagem , Humanos
20.
Sci Total Environ ; 651(Pt 2): 2312-2322, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30332664

RESUMO

The North China Plain (NCP) has experienced heavy air pollution in the past several decades featured by high levels of fine particulate matter (PM2.5). PM2.5 removal from the atmosphere in the NCP by dry deposition was estimated from 1999 through 2013 using the inferential method, which combined PM2.5 air concentrations retrieved from satellite remote sensing and dry deposition velocities (Vd) calculated using a bulk particle dry deposition model. Dry deposition of the three major inorganic ions in PM2.5, namely NH4+ (ammonium), NO3- (nitrate), and SO42- (sulfate), with their concentrations in 2000 and 2010 obtained from WRF-Chem model simulations, were also investigated considering their important roles in PM2.5 formation and ecosystem health. High levels of modeled and satellite-retrieved PM2.5 air concentrations, the secondary inorganic aerosols (the sum of NH4+, NO3-, and SO42-), and their respective deposition fluxes were identified from the southern NCP to Beijing-Tianjin metropolitans. The deposition fluxes derived from the inferential method and WRF-Chem increased considerably in the 2000s due to rising PM2.5 atmospheric levels across the NCP. The enhancement of dry deposition velocities of PM2.5 and three aerosol species in the NCP were associated nicely with increasing vegetation coverage and wind speed. We show that both air concentrations of PM2.5 and secondary inorganic aerosols and rising dry deposition velocities related to extensive afforestation activities contributed to their deposition fluxes and an inclining trend of PM2.5 removal from the atmosphere.

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