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1.
Materials (Basel) ; 13(17)2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32824967

RESUMO

The interest of this article lies in the sound radiation of shape memory alloy (SMA) composite laminates. Different from the traditional method of avoiding resonance sound radiation of composite laminates by means of structural parameter design, this paper explores the potential of adjusting the modal peak of the resonant acoustic radiation by using material characteristics of shape memory alloys (SMA), and provides a new idea for avoiding resonance sound radiation of composite laminates. For composite laminates embedded with pre-strained SMA, an innovation of vibration-acoustic modeling of SMA composite laminates considering pre-stain of SMA and thermal expansion force of graphite-epoxy resin is proposed. Based on the classical thin plate theory and Hamilton principle, the structural dynamic governing equation and the frequency equation of the laminates subjected to thermal environment are derived. The vibration sound radiation of composite laminates is calculated with Rayleigh integral. Effects of ambient temperature, pre-strain, SMA volume fraction, substrate ratio, and geometrical parameters on the sound radiation were analyzed. New laws of SMA material and pre-strain characteristics on sound radiation of composite laminates under temperature environment are revealed, which have theoretical and engineering functional significance for vibration and sound radiation control of SMA composite laminates.

2.
Int J Syst Evol Microbiol ; 70(6): 3839-3844, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32496184

RESUMO

A Gram-stain-negative bacterium, designated strain 501str8T, was isolated from a sediment sample collected from the East Pacific Ocean. 16S rRNA gene sequence analysis revealed that strain 501str8T belonged to the genus Muricauda, with closely related type strains Muricauda aquimarina SW-63T (98.5 %), Muricauda lutimaris SMK-108T (98.3 %) and Muricauda ruestringensis B1T (97.9 %). Up-to-date bacterial core gene set analysis revealed that strain 501str8T represented one independent lineage with M. aquimarina SW-63T. The average nucleotide identity values of strain 501str8T with M. aquimarina SW-63T and M. lutimaris SMK-108T were 80.2 and 81.3 %, respectively. In silico DNA-DNA hybridization values between strain 501str8T and M. aquimarina SW-63T and M. lutimaris SMK-108T were 22.8 and 32.9 %, respectively. The predominant isoprenoid quinone was menaquinone-6, and iso-C15 : 0, iso-C17 : 0 3-OH and iso-C15 : 1 G were the dominant cellular fatty acids. The G+C content of the genomic DNA was 42.8 mol%. Differential phylogenetic distinctiveness and chemotaxonomic differences, together with the phenotypic properties observed in this study, revealed that strain 501str8T could be differentiated from closely related species. Therefore, we propose that strain 501str8T represents a novel species of the genus Muricauda, for which the name Muricauda oceani sp. nov. is suggested. The type strain is 501str8T (=JCM 33902T=MCCC 1K04567T).


Assuntos
Flavobacteriaceae/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/isolamento & purificação , Hibridização de Ácido Nucleico , Oceano Pacífico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
3.
Int J Syst Evol Microbiol ; 70(7): 4345-4350, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32584750

RESUMO

A Gram-stain-negative bacterium, designated strain 40Bstr34T, isolated from a sediment sample from the West Pacific Ocean, was taxonomically characterized by using a polyphasic approach. The strain was phylogenetically close to Jiella aquimaris LZB041T and Jiella endophytica CBS5Q-3T, with 16S rRNA gene sequence similarities of 98.5 and 97.1 %, respectively. The genome of strain 40Bstr34T featured a G+C content of 65.7 % for a 5.8 Mb chromosome. Up-to-date bacterial core gene set analysis revealed that strain 40Bstr34T represents one independent lineage with J.aquimaris LZB041T. In silico DNA-DNA hybridization values between strain 40Bstr34T and its phylogenetic neighbours ranged from 30.3-34.2 %, below the cutoff of 70 %. In addition, the corresponding average nucleotide identity values were between 81.8-83.7 %, which are lower than 95 % threshold. The predominant cellular fatty acids of strain 40Bstr34T were summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c), cyclo-C19 : 0 ω8c and iso-C17 : 0 3-OH, and ubiquinone-10 as the predominant respiratory quinone. The major polar lipids included phosphatidylethanolamine, phosphatidylmonomethylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, two unidentified aminolipids and two unidentified lipids. Based on the results of phenotypic, chemotaxonomic and genetic analyses, strain 40Bstr34T is identified as representing a novel species of the genus Jiella for which the name Jiella pacifica sp. nov. is proposed. The type strain is 40Bstr34T (=JCM 33903T=MCCC 1K04569T).


Assuntos
Alphaproteobacteria/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Alphaproteobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Oceano Pacífico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
4.
Materials (Basel) ; 13(5)2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32121628

RESUMO

A gradient composite laminate that was composed of two­phase fibers, a shape memory alloy (SMA), and graphite was prepared to investigate modal performance and improve vibration behavior. The stress­strain relation of the single­layer composite plates was derived from Kirchhoff thin plate theory and the material constitutive of the SMA. A gradient distribution model and the eigenvalue equations of gradient composite laminates were developed. The influence of the fiber component content gradient distribution, pre­strain, the two­phase fiber volume fraction, and geometric parameters on the modal performance was analyzed. This study provides a method to avoid the structural resonance of composite laminates that are embedded with an SMA through the gradient distribution of two­phase fiber content that leads to the interaction of the material properties.

5.
Int J Syst Evol Microbiol ; 70(1): 340-345, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31596199

RESUMO

A Gram-stain-negative bacterium, designated IO390501T, was isolated from a sea water sample from the Indian Ocean and taxonomically characterized using a polyphasic approach. The strain is phylogenetically close to 'Devosia lucknowensis' L15 and Devosia chinhatensis IPL18T, with 16S rRNA gene sequence similarity of 97.7 and 97.4 %, respectively. The genome of IO390501T has a DNA G+C content of 61.9 mol% for the 3.9 Mb chromosome. Genome-based phylogenetic trees indicated that IO390501T clusters as an independent lineage with 'D. lucknowensis' L15. Genomic relatedness of in silico DNA-DNA hybridization between IO390501T and phylogenetic neighbours ranged from 18.8 to 21.5 %, below the cutoff of 70 %, and corresponding average nucleotide identity values were between 71.4 and 79.0 %, lower than the 95.0 % threshold. The predominant cellular fatty acids of IO390501T are summed feature 8 (C18 : 1ω7c/C18  : 1ω6c) and C16  :  0. IO390501T contains ubiquinone-10 as the sole respiratory quinone, and phosphatidylglycerol and glycolipids as the major polar lipids. On the basis of the results of phenotypic, chemotaxonomic and genetic analyses, strain IO390501T represents a novel species of the genus Devosia for which the name Devosia indica sp. nov. is proposed. The type strain is IO390501T.


Assuntos
Hyphomicrobiaceae/classificação , Filogenia , Água do Mar/microbiologia , Microbiologia da Água , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hyphomicrobiaceae/isolamento & purificação , Oceano Índico , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
6.
Antonie Van Leeuwenhoek ; 112(6): 927-933, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30737708

RESUMO

Strain IO390502T, isolated from surface seawater in the Indian Ocean, was characterised using a polyphasic taxonomy approach. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain IO390502T belongs to the genus Paracoccus and is closely related to Paracoccus seriniphilus DSM 14827T (97.6%), followed by P. zeaxanthinifaciens JCM 21774T (97.5%), P. homiensis DSM 17862T (97.3%), P. marcusii DSM 11574T (97.2%), P. haeundaensis BC 74171T (97.0%) and P. carotinifaciens E-396T (97.0%). Cells are Gram-negative, aerobic, poly-ß-hydroxybutyrate-accumulating, motile, rod-shaped, and forms creamy-white colonies. Optimal growth occurred at 25-30 °C, pH 5-8, and in the presence of 3-8% NaCl. The genome of strain IO390502T has a G+C content of 64.9 mol% and a 3.5 Mb chromosome. The in silico DNA-DNA hybridisation and average nucleotide identity values between strain IO390502T and the three closely related taxa, P. seriniphilus DSM 14827T, P. zeaxanthinifaciens JCM 21774T and P. homiensis DSM 17862T, are 19.6%, 21.9% and 20.6%, and 76.0%, 79.9% and 77.8%, respectively. Phosphatidylglycerol is the major lipid present, ubiquinone-10 (Q-10) is the sole isoprenoid quinone, and the major cellular fatty acid is C18:1ω7c. Based on data from phenotypic tests and genotypic differences between strain IO390502T and its close phylogenetic relatives, strain IO390502T represents a new species belonging to the genus Paracoccus, for which the name Paracoccus indicus sp. nov. is proposed. The type strain is IO390502T (= JCM 32637T = CCTCC AB 2018071T).


Assuntos
Paracoccus/isolamento & purificação , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Oceano Índico , Paracoccus/classificação , Paracoccus/genética , Paracoccus/metabolismo , Filogenia , RNA Ribossômico 16S/genética
7.
Accid Anal Prev ; 117: 318-327, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29753220

RESUMO

Inappropriate cruising speed, such as speeding, is one of the major contributors to the road safety, which increases both the quantitative number and severity of traffic accidents. Previous studies have indicated that traffic congestion is one of the primary causes of drivers' frustration and aggression, which may lead to inappropriate speed choice. In this study, the large taxi floating car data (FCD) was used to empirically evaluate how traffic congestion-related negative moods, defined as state aggressiveness, affected drivers' speed choice. The indirect effect of traffic delay on the cruising speed adjustment through the state aggressiveness was assessed through the mediation analysis. Furthermore, the moderated mediation analysis was performed to explore the effect of driver type, value of time, and working duration on the mediation role of state aggressiveness. The results proved that the state aggressiveness was the mediator of the relationship between travel delays and driving speed adjustment, and the mediation role was different across various driver types. As compared to the aggressive drivers, the normal drivers and the steady drivers tended to behave more aggressively after experiencing non-recurrent congestion during the early stage of the trips. When the value of time was high, steady drivers were more likely to adjust their speed choice although the effect was not statistically significant for other driver types. The validation results indicated that the speed model incorporating state aggressiveness could better predict the travel time than the traditional speed model that only considering the specific expected speed distribution. The prediction results for the manifest indicators of state aggressiveness, such as the maximum speed and the speed deviation, also demonstrated a reasonable reflection of the field data.


Assuntos
Agressão/psicologia , Condução de Veículo/psicologia , Comportamento de Escolha , Aglomeração/psicologia , Acidentes de Trânsito/prevenção & controle , Adulto , Condução de Veículo/estatística & dados numéricos , Automóveis/estatística & dados numéricos , Feminino , Humanos , Masculino , Modelos Estatísticos
8.
J Gastroenterol Hepatol ; 33(4): 774-780, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29293276

RESUMO

BACKGROUND AND AIM: The aim of our study was to investigate the immunomodulatory effect and short-term efficacy and long-term prognosis of decompensated liver cirrhosis patients caused by hepatitis B after a double transplantation with human umbilical cord mesenchymal stem cells (hUCMSCs). METHODS: Fifty inpatients were recruited and given the same medical treatments, receiving hUCMSCs injection intravenously. Fifty-three patients (Group B) matched for age, sex, and baseline alanine aminotransferase, aspartate aminotransferase, albumin, total bilirubin, prothrombin time, and model for end-stage liver disease score and Child-Pugh classification, acted as the control group. RESULTS: Interleukin-6 and tumor necrosis factor alpha levels markedly decreased, and interleukin-10 level apparently increased in Group A at 2 and 4 weeks after treatment. Transforming growth factor beta in Group A increased more remarkably at 2 weeks after treatment. T4 cells and Treg cells in Group A were apparently higher than those in Group B at 2 and 4 weeks after treatment, and T8 cells and B cells were significantly lower than those in Group B. Aspartate aminotransferase levels in Group A were dramatically declining at 8 and 12 weeks after treatment. Levels of albumin, total bilirubin, and prothrombin time in Group A were apparently improved from 4 to 12 weeks after treatment. The improvements in model for end-stage liver disease and Child-Pugh scores in Group A were notably superior to those in Group B from 4 to 36 weeks after treatment. There were no remarkable differences in the incidence of developing liver failure throughout the follow-up period, but the mortality rate of Group A was lower than that of Group B. CONCLUSION: This therapeutic method may be an appropriate choice for patients with decompensated liver cirrhosis.


Assuntos
Hepatite B Crônica/complicações , Cirrose Hepática/imunologia , Cirrose Hepática/terapia , Subpopulações de Linfócitos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Cordão Umbilical/citologia , Adulto , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Biomarcadores/sangue , Citocinas/sangue , Feminino , Humanos , Cirrose Hepática/diagnóstico , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Tempo de Protrombina , Resultado do Tratamento
9.
Traffic Inj Prev ; 19(3): 311-316, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29045160

RESUMO

OBJECTIVE: The 3 objectives of this study are to (1) identify the driving style characteristics of taxi drivers in Shanghai and New York City (NYC) using taxi Global Positioning System (GPS) data and make a comparative analysis; (2) explore the influence of different driving style characteristics on the frequency of speeding (who and how?) and (3) explore the influence of driving style characteristics, road attributes, and environmental factors on the speeding rate (when, where, and how?) Methods: This study proposes a driver-road-environment identification (DREI) method to investigate the determinant factors of taxi speeding violations. Driving style characteristics, together with road and environment variables, were obtained based on the GPS data and auxiliary spatiotemporal data in Shanghai and NYC. RESULTS: The daily working hours of taxi drivers in Shanghai (18.6 h) was far more than in NYC (8.5 h). The average occupancy speed of taxi drivers in Shanghai (21.3 km/h) was similar to that of NYC (20.3 km/h). Speeders in both cities had shorter working hours and longer daily driving distance than other taxi drivers, though their daily income was similar. Speeding drivers routinely took long-distance trips (>10 km) and preferred relatively faster routes. Length of segments (1.0-1.5 km) and good traffic condition were associated with high speeding rates, whereas central business district area and secondary road were associated with low speeding rates. Moreover, many speeding violations were identified between 4:00 a.m. and 7:00 a.m. in both Shanghai and NYC and the worst period was between 5:00 a.m. and 6:00 a.m. in both cities. CONCLUSIONS: Characteristics of drivers, road attributes, and environment variables should be considered together when studying driver speeding behavior. Findings of this study may assist in stipulating relevant laws and regulations such as stricter offense monitoring in the early morning, long segment supervision, shift rule regulation, and working hour restriction to mitigate the risk of potential crashes.


Assuntos
Aceleração , Acidentes de Trânsito/estatística & dados numéricos , Condução de Veículo/estatística & dados numéricos , Automóveis/estatística & dados numéricos , Assunção de Riscos , Adulto , China , Feminino , Humanos , Masculino , Cidade de Nova Iorque , Fatores de Risco , Sensação
10.
Med Sci Monit ; 23: 3904-3912, 2017 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-28802099

RESUMO

BACKGROUND Cancer-associated fibroblasts (CAFs) are key factors in malignant tumor initiation, progression, and metastasis. However, the effect of CAFs autophagy on triple-negative breast cancer (TNBC) cells is not clear. In this study, the growth effect of TNBC cells regulated by CAFs autophagy was evaluated. MATERIAL AND METHODS CAFs were obtained from invasive TNBC tumors and identified by Western blot and immunofluorescence staining assay. CAFs were co-cultured with TNBC cells, and migration and invasion were evaluated by Matrigel-coated Transwell and Transwell inserts. TNBC cells growth was detected by MTT assay, and epithelial-mesenchymal transition (EMT) regulated by CAFs was evaluated by Western blot assay. RESULTS CAFs were identified by the high expression of α-smooth muscle actin (α-SMA) protein. Autophagy-relevant Beclin 1 and LC3-II/I protein conversion levels in CAFs were higher than those in NFs (P<0.05). TNBC cells migration, invasion, and proliferation levels were significantly improved in the CAFs-conditioned medium (CAFs-CM) group, compared with the other 3 groups (P<0.05). TNBC cells vimentin and N-cadherin protein levels were upregulated and E-cadherin protein level was downregulated in the CAFs-CM group compared with the control group (P<0.05). Further study indicated b-catenin and P-GSK-3ß protein levels, which are the key proteins in the Wnt/ß-catenin pathway, were upregulated in the CAFs-CM group compared with the control group (P<0.05). CONCLUSIONS Our data demonstrated CAFs autophagy can enhance TNBC cell migration, invasion, and proliferation, and CAFs autophagy can induce TNBC cells to engage in the EMT process through the Wnt/ß-catenin pathway.


Assuntos
Actinas/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Actinas/análise , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Caderinas/metabolismo , Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/fisiologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , China , Progressão da Doença , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Fibroblastos/efeitos dos fármacos , Humanos , Miócitos de Músculo Liso/metabolismo , Neoplasias de Mama Triplo Negativas/fisiopatologia , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/efeitos dos fármacos , beta Catenina/metabolismo
11.
Int J Clin Exp Med ; 8(5): 7049-58, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26221242

RESUMO

Beclin 1 is a promoter gene for autophagy as well as a key factor for regulating tumor cell growth and death. Allelic deletion of Beclin 1 has been observed in certain triple-negative breat cancer (TNBC) cells, and it might be associated with increased proliferation and invasion in TNBC cells. In this study we investigated the relationship between Beclin 1 expression and prognosis for TNBC patients, as well as the influence on cell growth by Beclin 1 overexpression in different cultural conditions. Beclin 1 expression in TNBC tissues was measured by immunohistochemical staining and correlated with clinicopathologic parameters for TNBC patients. The plasmid of pDS-RED-C1-Beclin 1 was transfected to BT-549 and MDA-MB-231 cells and autophagy, proliferation, apoptosis, cell cycle and Epithelial-mesenchymal transition (EMT) process were measured. Results indicated that high level of Beclin 1 expression was correlated with more lymph nodes and distant metastasis but unrelated to survival rates in 5 years for TNBC patients. In vitro, overexpression of Beclin 1 improved cellular autophagy in both BT-549 and MDA-MB-231 cells, inhibited cell proliferation at normal cultural condition and increased cell survival in starvation, hypoxia or with doxorubicin stimulation. Besides, Beclin 1 overexpression decreased cell apoptosis, induced cells to be in G0/G1 phase and promoted EMT process through Wnt/ß-catenin pathway in starvation. Thus, Beclin 1 overexpression plays a double role in BT-549 and MDA-MB-231 cell growth by elevating the capability of autophagy. These findings might be useful for searching a proper method for clinical therapy of TNBC from the aspect of autophagy in future.

12.
Nan Fang Yi Ke Da Xue Xue Bao ; 31(3): 392-6, 2011 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-21421469

RESUMO

OBJECTIVE: To establish the BGC-823/WTX-EGFP gastric cancer cell line with stable expression of Wilms tumor gene on the X chromosome (MTX) for functional analysis of WTX gene. METHODS: The full-length WTX cDNA was amplified from human embryonic kidney 293FT cells and cloned into the pEGFP-N1 vector containing the reporter gene of green fluorescence protein. The recombinant pEGFP-WTX expression vector, after digestion by restriction enzyme to identify the size of target gene fragment, was transfected into 293FT cells and the expression of fluorescent reporter gene was observed under fluorescence microscope. pEGFP-WTX vector was transfected into human gastric cancer BGC-823 cell line to establish BGC-823/WTX-EGFP cell line stably expressing WTX. Quantitative RT-PCR and immunocytochemical staining were used to detect the expression of WTX in both BGC-823/WTX-EGFP and control BGC-823 cells. RESULTS: The recombinant pEGFP-WTX plasmid was successfully constructed and verified by PCR and sequencing. The mRNA and protein expressions of MTX were significantly increased in BGC-823/WTX-EGFP cells as compared with those in the control cells. CONCLUSION: The full-length WTX expression vector (pEGFP-WTX) and BGC-823/WTX-EGFP gastric cancer cell line have been successfully established to facilitate further functional study of WTX gene.


Assuntos
Linhagem Celular Tumoral , Genes do Tumor de Wilms , Vetores Genéticos , Neoplasias Gástricas/genética , Linhagem Celular , Cromossomos Humanos X/genética , Enzimas de Restrição do DNA , DNA Complementar , Proteínas de Fluorescência Verde/genética , Humanos , Plasmídeos , Transfecção
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