Associated with the concepts of the Lp-mixed quermassintegrals, the Lp-mixed volume, and the Lp-dual mixed volume, we establish inequalities for the quermassintegrals of the Lp-projection body and the Lp-centroid body...Associated with the concepts of the Lp-mixed quermassintegrals, the Lp-mixed volume, and the Lp-dual mixed volume, we establish inequalities for the quermassintegrals of the Lp-projection body and the Lp-centroid body. Further, the general results for the Shephard problem of the Lp-projection body and the Lp-centroid body are obtained.展开更多
The community La Llave, Queretaro State, Mexico, has not been identified by the sanitary authorities as living in a hazard area related to dental fluorosis. However;a high concentration of fluoride is found in their d...The community La Llave, Queretaro State, Mexico, has not been identified by the sanitary authorities as living in a hazard area related to dental fluorosis. However;a high concentration of fluoride is found in their drinking water causing them dental fluorosis. Physical-chemical analysis was carried out in the groundwater sources to determine the prevalence of dental fluorosis risk and caries accordingly to criteria of The World Health Organization, and 154 school children of ages 10 to 13 years were examined. As a result, 1.9 mg/L of fluorine concentration in drinking water was obtained;dental fluorosis presence was detected in the school children with an incidence of about 98%, in 47% of cases severe fluorosis with a dental caries index of 3.06 was traced. The groundwater sources in La Llave community contains fluorine above the limits dictated by Mexican regulations, producing serious repercussions on the health of school children, with an unnaturally high incidence of dental fluorosis.展开更多
OBJECTIVE Dengue virus belongs to the Flaviviridaefamily,and causes dengue fever and its related complications.Currently,there are no antiviral agents or licensed vaccines against dengue in humans.Houttuyniacordata Th...OBJECTIVE Dengue virus belongs to the Flaviviridaefamily,and causes dengue fever and its related complications.Currently,there are no antiviral agents or licensed vaccines against dengue in humans.Houttuyniacordata Thunb.(Saururaceae)is documented to possess antiviral activity against several medically important viruses.METHODS The in vitro activities of the total ethyl acetate(EA)extracts of two batches of H.cordata,five EA fractions,and four of its constituent polyphenols(chlorogenic acid,hyperoside,quercetin,and quercitrin)against the new guinea C strain of dengue-2 virus were investigated.RESULTS Using the plaque reduction test,the total EA extracts of H.cordatainhibited viral infectivity when pre-incubated with virus before the viral adsorption stage,but exhibited no dose-dependent response when added to the cells at 6h post-infection.The 50% inhibitory concentration(IC50)of total EA extracts from two batches of H.cordata added before the viral adsorption stage were 0.24±3.1μg·mL-1 and 0.04±4.6μg·mL-1.However,only one out of five tested EA fractions showed considerably- weaker IC50 of 333μg·mL1.The pure polyphenol compounds displayed some anti-dengue activity,with their combinations yielding greater antiviral effects,especially the combination of chlorogenic acid and hyperoside with a high selectivity index.However,the enhanced efficacy of the polyphenol combinations was still less than that of the total EA extracts which revealed absence of cytotoxicity.Therefore,there may be other compounds in H.cordatathat contribute to the superior efficacy of the EA extracts.CONCLUSION We conclude that H.cordata possesses anti-dengue-2 virus activity,and harbors potential for the development of antiviral agents against dengue.展开更多
This paper reviews the importance of visibility in public deliberation in the theoretical construction of political communication. Political communication is the area that study social and political interactions of ac...This paper reviews the importance of visibility in public deliberation in the theoretical construction of political communication. Political communication is the area that study social and political interactions of actors through discourses and practices within the public sphere. The social and political actors manage their public appearances in an exercise of visibility, allowing deliberation of public affairs. In recent years, Mexico has been a relevant case of study for understanding the opening of media into the public discussion of governmental affairs. As an example, this paper presents an analysis of public deliberation in the city of Quer6taro, Mexico. This study analyses political participation and openness of media, based on the concepts visibility, public sphere and citizenship. The analysis was built on the idea that the press concentrates most of the issues of public interest and that it reflects actors and arguments given for deliberation. In a qualitative approximation, we analyzed the discourses published in four journals and developed an analytical framework that illustrates the levels of access and visibility of a variety of political and social actors. This exercise demonstrates the importance of the concept of visibility in public deliberation and the media as managers in the current configuration of political communication.展开更多
基金Sponsored by the Natural Science Foundation of China (10671117)Academic Mainstay Foundation of Hubei Province of China (D200729002)Science Foundation of China Three Gorges University
文摘Associated with the concepts of the Lp-mixed quermassintegrals, the Lp-mixed volume, and the Lp-dual mixed volume, we establish inequalities for the quermassintegrals of the Lp-projection body and the Lp-centroid body. Further, the general results for the Shephard problem of the Lp-projection body and the Lp-centroid body are obtained.
文摘The community La Llave, Queretaro State, Mexico, has not been identified by the sanitary authorities as living in a hazard area related to dental fluorosis. However;a high concentration of fluoride is found in their drinking water causing them dental fluorosis. Physical-chemical analysis was carried out in the groundwater sources to determine the prevalence of dental fluorosis risk and caries accordingly to criteria of The World Health Organization, and 154 school children of ages 10 to 13 years were examined. As a result, 1.9 mg/L of fluorine concentration in drinking water was obtained;dental fluorosis presence was detected in the school children with an incidence of about 98%, in 47% of cases severe fluorosis with a dental caries index of 3.06 was traced. The groundwater sources in La Llave community contains fluorine above the limits dictated by Mexican regulations, producing serious repercussions on the health of school children, with an unnaturally high incidence of dental fluorosis.
基金The project supported by a research grant from the National University of Singapore
文摘OBJECTIVE Dengue virus belongs to the Flaviviridaefamily,and causes dengue fever and its related complications.Currently,there are no antiviral agents or licensed vaccines against dengue in humans.Houttuyniacordata Thunb.(Saururaceae)is documented to possess antiviral activity against several medically important viruses.METHODS The in vitro activities of the total ethyl acetate(EA)extracts of two batches of H.cordata,five EA fractions,and four of its constituent polyphenols(chlorogenic acid,hyperoside,quercetin,and quercitrin)against the new guinea C strain of dengue-2 virus were investigated.RESULTS Using the plaque reduction test,the total EA extracts of H.cordatainhibited viral infectivity when pre-incubated with virus before the viral adsorption stage,but exhibited no dose-dependent response when added to the cells at 6h post-infection.The 50% inhibitory concentration(IC50)of total EA extracts from two batches of H.cordata added before the viral adsorption stage were 0.24±3.1μg·mL-1 and 0.04±4.6μg·mL-1.However,only one out of five tested EA fractions showed considerably- weaker IC50 of 333μg·mL1.The pure polyphenol compounds displayed some anti-dengue activity,with their combinations yielding greater antiviral effects,especially the combination of chlorogenic acid and hyperoside with a high selectivity index.However,the enhanced efficacy of the polyphenol combinations was still less than that of the total EA extracts which revealed absence of cytotoxicity.Therefore,there may be other compounds in H.cordatathat contribute to the superior efficacy of the EA extracts.CONCLUSION We conclude that H.cordata possesses anti-dengue-2 virus activity,and harbors potential for the development of antiviral agents against dengue.
文摘This paper reviews the importance of visibility in public deliberation in the theoretical construction of political communication. Political communication is the area that study social and political interactions of actors through discourses and practices within the public sphere. The social and political actors manage their public appearances in an exercise of visibility, allowing deliberation of public affairs. In recent years, Mexico has been a relevant case of study for understanding the opening of media into the public discussion of governmental affairs. As an example, this paper presents an analysis of public deliberation in the city of Quer6taro, Mexico. This study analyses political participation and openness of media, based on the concepts visibility, public sphere and citizenship. The analysis was built on the idea that the press concentrates most of the issues of public interest and that it reflects actors and arguments given for deliberation. In a qualitative approximation, we analyzed the discourses published in four journals and developed an analytical framework that illustrates the levels of access and visibility of a variety of political and social actors. This exercise demonstrates the importance of the concept of visibility in public deliberation and the media as managers in the current configuration of political communication.
