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1.
Sci Rep ; 14(1): 5253, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438518

RESUMO

Chisel pick is a basic and important rock cutting tool, and the performance of chisel pick directly affects rock mining. In this paper, a rock cutting device was developed for chisel picks cutting experiments. The influence of the depth of cutting, width of chisel pick, rake angle, back clearance angle and tip fillet radius on the cutting performance such as cutting force, normal force, and specific energy has been comprehensively studied. In addition to the general conclusions, the experimental results show that the back clearance angle has an influence range on the cutting, and the ratio of the normal force to the cutting force decreases with the increase of the rake angle; the tip fillet radius greatly improve the mean cutting force and specific energy. The experimental results will provide data support for the design of chisel picks on rock excavation machinery and a more reasonable chisel pick cutting rock mechanics model.

2.
Front Microbiol ; 15: 1354823, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500584

RESUMO

Objective: Previous studies have indicated that diarrhea with kidney-yang deficiency syndrome leads to a disorder of small intestine contents and mucosal microbiota. However, the relationship of TMA-lyase (CutC) activity and TMAO with diarrhea with kidney-yang deficiency syndrome remains unexplored. Therefore, this study explores the relationship between cecal microbiota and choline TMA-lyase (CutC) activity, as well as the correlation between trimethylamine oxide (TMAO), inflammatory index, and CutC activity. Method: Twenty SPF-grade male KM mice were randomly divided into the normal group (CN) and the diarrhea model group (CD). Diarrhea mouse models were established by adenine combined with Folium sennae administration. CutC activity, TMAO, interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) levels were detected, and the cecal content microbiota was sequenced. Result: After 14 days, diarrhea occurred in the CD group. Compared with the CN group, there was no significant change in the activity of CutC in the small intestine of the CD group, while the activity of CutC in the cecum was significantly increased, and the levels of TMAO, IL-6, and TNF-α showed a significant increase. The Chao1 index, Observed_species index, Shannon index, and Simpson index all exhibited a decreasing trend. The main changes at the bacterial genus level were Alistipes, Enterorhabdus, Desulfovibrio, Bacteroides, Candidatus_Saccharimonas, and [Ruminococcus]_torques_group. The results of LEfSe analysis, random forest analysis and ROC curve analysis revealed Paludicola, Blautia, Negativibacillus, Paraprevotella, Harryflintia, Candidatus_Soleaferrea, Anaerotruncus, Oscillibacter, Colidextribacter, [Ruminococcus]_torques_group, and Bacteroides as characteristic bacteria in the CD group. Correlation analysis showed a significant negative correlation between cecal CutC activity and Ligilactobacillus, and a significant positive correlation with Negativibacillus and Paludicola. The level of TMAO was significantly positively correlated with CutC activity and IL-6. Conclusion: Diarrhea with kidney-yang deficiency syndrome significantly affects the physiological status, digestive enzyme activity, CutC activity, TMAO levels, and inflammatory response in mice. Additionally, there are changes in the composition and function of cecal microbiota, indicating an important impact of diarrhea with kidney-yang deficiency syndrome on the host intestinal microbiota balance. The occurrence of diarrhea with kidney-yang deficiency syndrome may be associated with dysbiosis of intestinal microbiota, increased CutC activity, elevated TMAO levels, and heightened inflammatory factor levels.

3.
PLoS One ; 13(1): e0191466, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29364936

RESUMO

Lane-changing (LC) behavior is investigated on Chinese freeways, where the driving circumstances are relatively aggressive. Three data sets were collected from urban expressways and an intercity highway in the form of traffic videos. Different aspects of LC behaviors are analyzed, i.e., the LC rate, motivation, target lane choice and impact on traffic. The results suggest that LC is a transient behavior that randomly occurs with high frequency, which is the main feature of aggressive driving. Several LC patterns and the combination effect of ramps, fast lanes and various vehicle types are presented. The influence of LC on local traffic endures for approximately 15 to 30 s, which rapidly increases and slowly declines. LC behavior will increase the risk of high-speed car-following. All results are obtained from the empirical data; they will be useful for traffic management and traffic modeling.


Assuntos
Condução de Veículo/psicologia , Acidentes de Trânsito/prevenção & controle , Acidentes de Trânsito/psicologia , Agressão , Condução de Veículo/estatística & dados numéricos , Comportamento , China , Humanos , Modelos Psicológicos , Motivação , Gestão da Segurança , População Urbana , Gravação em Vídeo
4.
Int J Med Mushrooms ; 18(4): 327-36, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27481299

RESUMO

In this study, the main bioactive compounds of the fruit bodies of Cordyceps militaris-such as adenosine, cordycepin, polysaccharides, mannitol, superoxide dismutase (SOD), and carotenoids-were cultivated on wheat and pupae, as well as sclerotium (the pupae portion) and sclerotium with fruiting bodies. The amounts of adenosine and polysaccharide in all the tested samples (except for the polysaccharides of sclerotium) are higher than the quality standards (adenosine ≥0.055% and polysaccharide ≥2.5%) determined by the Ministry of Health of the People's Republic of China. As the most important bioactive compound in C. militaris, cordycepin is the highest in the fruiting bodies on pupae than in other samples, whereas it is the lowest in the sclerotium. The amounts of cordycepin, carotenoids, and SOD were higher in the fruiting bodies on pupae than that in the fruiting bodies on wheat, whereas the amounts of adenosine, polysaccharides, and mannitol were higher in the fruiting bodies on wheat than in the fruiting bodies on pupae. There was no significant difference in the amounts of cordycepin, carotenoids, and SOD in the sclerotium with fruiting bodies and the fruiting bodies on wheat. The adenosine, polysaccharide, and mannitol contents in the sclerotium with fruiting bodies were significantly lower than those of the fruiting bodies on wheat. Overall, the results of this evaluation could not distinguish which is better: the fruiting bodies on pupae or those on wheat; each has its own merits. The fruiting bodies of C. militaris cultivated on both wheat and pupae are important candidates for medicinal and tonic use for the welfare of humankind.


Assuntos
Cordyceps/química , Carpóforos/química , Pupa/microbiologia , Triticum/microbiologia , Adenosina/análise , Animais , Desoxiadenosinas/análise , Manitol/análise , Polissacarídeos/análise , Superóxido Dismutase/metabolismo
5.
Appl Microbiol Biotechnol ; 100(2): 743-55, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26476643

RESUMO

Light is an essential factor for pigment formation and fruit body development in Cordyceps militaris, a well-known edible and medicinal fungus. Cmwc-1, a homolog of the blue-light receptor gene white collar-1 (wc-1) in Neurospora crassa, was cloned from the C. militaris genome in our previous study. Here, Cmwc-1 gene inactivation results in thicker aerial hyphae, disordered fruit body development, a significant reduction in conidial formation, and carotenoid and cordycepin production. These characteristics were restored when the ΔCmwc-1 strains were hybridized with wild-type strains of the opposite mating type. A genome-wide expression analysis revealed that there were 1042 light-responsive genes in the wild-type strain and only 458 in the ΔCmwc-1 strain. Among five putative photoreceptors identified, Vivid, cryptochrome-1, and cyclobutane pyrimidine dimer photolyase are strongly induced by light in a Cmwc-1-dependent manner, while phytochrome and cryptochrome-2 were not induced. The transcription factors involved in the fungal light reaction were mainly of the Zn2Cys6 type. CmWC-1 regulates adenylosuccinate synthase, an important enzyme for adenosine de novo synthesis, which could explain the reduction in cordycepin production. Some G protein-coupled receptors that control fungal fruit body formation and the sexual cycle were regulated by CmWC-1, and the cAMP pathway involved in light signal transduction in N. crassa was not critical for the photoreaction in the fungus here. A transcriptional analysis indicated that steroid biosynthesis was more active in the ΔCmwc-1 strain, suggesting that CmWC-1 might switch the vegetative growth state to primordia differentiation by suppressing the expression of related genes.


Assuntos
Cordyceps/crescimento & desenvolvimento , Cordyceps/metabolismo , Carpóforos/crescimento & desenvolvimento , Genes Fúngicos , Fotorreceptores Microbianos/genética , Fotorreceptores Microbianos/metabolismo , Carotenoides/metabolismo , Cordyceps/genética , Desoxiadenosinas/metabolismo , Carpóforos/genética , Carpóforos/metabolismo , Perfilação da Expressão Gênica , Genoma Fúngico , Luz , Neurospora crassa/genética , Metabolismo Secundário , Esteroides/biossíntese , Fatores de Transcrição/metabolismo
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