Using fully reactive molecular dynamics methodologies we investigated the structural and dynamical aspects of the fluorination mechanism leading to fluorographene formation from graphene membranes. fluorination tends ...
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Using fully reactive molecular dynamics methodologies we investigated the structural and dynamical aspects of the fluorination mechanism leading to fluorographene formation from graphene membranes. fluorination tends to produce significant defective areas on the membranes with variation on the typical carbon-carbon distances, sometimes with the presence of large holes due to carbon losses. The results obtained in our simulations are in good agreement with the broad distribution of values for the lattice parameter experimentally observed. We have also investigated mixed atmospheres composed by H and f atoms. When H is present in small quantities an expressive reduction on the rate of incorporation offluorine was observed. On the other hand when fluorine atoms are present in small quantities in a hydrogen atmosphere, they induce an increasing on the hydrogen incorporation and the formation of locally self-organized structure of adsorbed H and f atoms.
Known for leadership in design, progressive manufacturing methods and expertise in global sourcing, Pulaski furniture has steadily created its reputation and pro le over the last 50 years.
Known for leadership in design, progressive manufacturing methods and expertise in global sourcing, Pulaski furniture has steadily created its reputation and pro le over the last 50 years.
P>Aims To determine the effect of nicotine, cotinine and cigarette smoke extract (CSE) on the neutrophil respiratory burst and their effect on activation of the nuclear factor-kappa B (Nf kappa B) pathway in oral e...
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P>Aims To determine the effect of nicotine, cotinine and cigarette smoke extract (CSE) on the neutrophil respiratory burst and their effect on activation of the nuclear factor-kappa B (Nf kappa B) pathway in oral epithelium. Materials and Methods Neutrophils from periodontally healthy individuals were treated with nicotine, cotinine and CSE before stimulation with fusobacterium nucleatum, IgG-opsonized Staphylococcus aureus and Escherichia coli lipopolysaccharide. Total and extracellular reactive oxygen species (ROS) generation was determined by luminol/isoluminol chemiluminescence. Activation of Nf kappa B in oral epithelial cells was determined by immunocytochemistry. Results Smoke extract alone caused increased neutrophil extracellular isoluminol-dependent chemiluminescence, not detectable with luminol. However, pre-treatment with smoke extract reduced both total and extracellular ROS generation in response to all stimuli. Nicotine and cotinine had no effect on the neutrophil respiratory burst. Smoke extract, nicotine and cotinine did not induce oral epithelial cell Nf kappa B activation. Conclusions These data demonstrate that smoke extract reduces the ability of neutrophils to generate ROS after stimulation with f. nucleatum and IgG-opsonized S. aureus but, at high concentrations, stimulates extracellular ROS generation. During periodontitis, cigarette smoking may differentially affect neutrophil function, generally preventing elimination of periodontal pathogens but, in heavy smokers, also stimulating ROS release and oxidative stress mediated tissue damage.
Objectives: Delayed first-stage palliation of children with hypoplastic left heart syndrome and related pathologies can be associated with poor outcomes because of development of progressive pulmonary vascular disease...
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Objectives: Delayed first-stage palliation of children with hypoplastic left heart syndrome and related pathologies can be associated with poor outcomes because of development of progressive pulmonary vascular disease and volume load effects on the systemic ventricle and atrioventricular valve. We examine the current era's survival in this subgroup. Methods: fifty-five infants older than 2 weeks underwent the Norwood operation (2003-2007). Separate competing risk analyses were performed to model outcomes (death and transition to the next stage) after the Norwood operation and after bidirectional cavopulmonary connection. Results: Median age was 32 days (range, 15-118 days). forty-seven percent had hypoplastic left heart syndrome, and 53% had other complex univentricular variants. Mean ascending aortic size was 4.4 +/- 1.9 mm, 10% had impaired ventricular function, 11% had moderate atrioventricular valve regurgitation, and 32% had restrictive pulmonary venous return. Pulmonary blood flow was established through an aortopulmonary shunt (n - 30) or Sano shunt (n = 25). After the Norwood operation, patients required longer ventilation and more oxygen and nitric oxide and had higher inotropic scores compared with those undergoing the traditional management protocol. Competing risks analysis showed that 2 years after the Norwood operation, 39% had died, and 57% underwent bidirectional cavopulmonary connection. four years after bidirectional cavopulmonary connection, 15% had died, and 85% underwent the fontan operation. Overall 3-year survival after the Norwood operation was 53%. factors associated with mortality were age, lower weight at the time of the Norwood operation, impaired ventricular function, longer circulatory arrest, and lower pre-bidirectional cavopulmonary connection saturation. Conclusions: Children older than 2 weeks undergoing the Norwood operation frequently require postoperative pulmonary vasodilatation and high inotropic support. A significant hazard o
fungal metabolites are attracting attention as potential microbial insecticides, and they are anticipated to overcome the problems of pesticide resistance and environmental pollution that are associated with the indis...
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fungal metabolites are attracting attention as potential microbial insecticides, and they are anticipated to overcome the problems of pesticide resistance and environmental pollution that are associated with the indiscriminate use of conventional synthetic insecticides. The relative bioefficacies of selected fungal pathogens, Aspergillus flavus, A. niger, A. parasiticus, fusarium sporotrichoides and Penicillium verrucosum were observed against Anopheles stephensi and Culex quinquefasciatus larvae. A. flavus demonstrated the greatest bioefficacy with 50% lethal concentration (LC50) values of 9.54 and 10.98 ppm against Anopheles stephensi and Culex quinquefasciatus larvae, respectively, after 24-h exposure. The bioefficacy of A. flavus increased in both species with an exposure time of 48 h, with LC50 values of 7.26 and 8.55 ppm, respectively.
Activity-guided fractionation of the stems of Marsdenia tenacissima led to the isolation offive new pregnane glycosides, namely marstenacissides E (1), f (2), G (3), H (4), and I (5). Their structures were determined...
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Activity-guided fractionation of the stems of Marsdenia tenacissima led to the isolation offive new pregnane glycosides, namely marstenacissides E (1), f (2), G (3), H (4), and I (5). Their structures were determined on the basis of 1H and 13C NMR, COSY, TOCSY, ROESY, and fABMS experiments.
The new rural cooperative medical system has achieved periodical achievements since its ***,there are many factors hampering the development of the new system,such as the high cost,the difficulties in fund procurement...
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The new rural cooperative medical system has achieved periodical achievements since its ***,there are many factors hampering the development of the new system,such as the high cost,the difficulties in fund procurement,the lack of management,the narrow coverage of benefit,the ineffective constraint to the designated medical institutions,the high fund balance rate,and the poor medical facilities and services in rural *** are put forward to solve these problems,including improving the system design,expanding the coverage of the system,expanding the fund sources,reducing the financing costs,strengthening the fund supervision,enhancing the supervision of designated medical institutions,and improving the capacity of health services in rural areas.
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