To obtain the caries experience and,plaque accumulation severity and pit and fissure morphology in first permanent molars in 7-8 children in Wuhan,as a reasonable prediction of caries risk and preventive attention in ...To obtain the caries experience and,plaque accumulation severity and pit and fissure morphology in first permanent molars in 7-8 children in Wuhan,as a reasonable prediction of caries risk and preventive attention in the future,a convenient sample of five primary schools in the vicinity of the Wuhan University School and Hospital of Stomatology was drawn.Two calibrated examiners orally examined all present grade 2 children in the classroom,using standard caries plaque and tooth morphology criteria.Dental caries was scored at enamel(D 2) and dentine(D 3) for tooth and surface level.Independent variables were age,gender and school.Data analysis used analysis of variance and t-test.The sample comprised 1 043 7-and 8-year-olds.The prevalence of dental caries in permanent dentition was 8.7% and in primary dentition,68.7%.Mean Decayed,Missing,Filled Teeth/S(DMFT/S) scores were 0.11 and 0.14,respectively.Mean dmft/s scores were 2.8 and 5.0.The d-component constituted 75% of the d 3 mft index,while enamel carious lesions constituted 36% of the total number of carious lesions(d 2,3-component).Prevalence of medium and deep pits and fissures was 84.6%.Prevalence of medium and severe plaque accumulation was 67.4%.Prevalence of dental caries in the deciduous and permanent dentitions of 7-to 8-year-old children was high.Deep pits and fissures in high caries risk children should be sealed.展开更多
We investigate the quantum entanglement in a double-cavity optomechanical system consisting of an optomechanical cavity and an auxiliary cavity,where the optomechanical cavity mode couples with the mechanical mode via...We investigate the quantum entanglement in a double-cavity optomechanical system consisting of an optomechanical cavity and an auxiliary cavity,where the optomechanical cavity mode couples with the mechanical mode via radiation-pressure interaction,and simultaneously couples with the auxiliary cavity mode via nonreciprocal coupling.We study the entanglement between the mechanical oscillator and the cavity modes when the two cavities are reciprocally or non-reciprocally coupled.The logarithmic negativity E_(n)^((1))(E_(n)^((2)))is adopted to describe the entanglement degree between the mechanical mode and the optomechanical cavity mode(the auxiliary cavity mode).We find that both E_(n)^((1))and E_(n)^((2))have maximum values in the case of reciprocal coupling.By using nonreciprocal coupling,E_(n)^((1))and E_(n)^((2))can exceed those maximum values,and a wider detuning region where the entanglement exists can be obtained.Moreover,the entanglement robustness with respect to the environment temperature is also effectively enhanced.展开更多
文摘To obtain the caries experience and,plaque accumulation severity and pit and fissure morphology in first permanent molars in 7-8 children in Wuhan,as a reasonable prediction of caries risk and preventive attention in the future,a convenient sample of five primary schools in the vicinity of the Wuhan University School and Hospital of Stomatology was drawn.Two calibrated examiners orally examined all present grade 2 children in the classroom,using standard caries plaque and tooth morphology criteria.Dental caries was scored at enamel(D 2) and dentine(D 3) for tooth and surface level.Independent variables were age,gender and school.Data analysis used analysis of variance and t-test.The sample comprised 1 043 7-and 8-year-olds.The prevalence of dental caries in permanent dentition was 8.7% and in primary dentition,68.7%.Mean Decayed,Missing,Filled Teeth/S(DMFT/S) scores were 0.11 and 0.14,respectively.Mean dmft/s scores were 2.8 and 5.0.The d-component constituted 75% of the d 3 mft index,while enamel carious lesions constituted 36% of the total number of carious lesions(d 2,3-component).Prevalence of medium and deep pits and fissures was 84.6%.Prevalence of medium and severe plaque accumulation was 67.4%.Prevalence of dental caries in the deciduous and permanent dentitions of 7-to 8-year-old children was high.Deep pits and fissures in high caries risk children should be sealed.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12047520,61941501,61775062,11574092,61378012,91121023,62071186 and 61771205).
文摘We investigate the quantum entanglement in a double-cavity optomechanical system consisting of an optomechanical cavity and an auxiliary cavity,where the optomechanical cavity mode couples with the mechanical mode via radiation-pressure interaction,and simultaneously couples with the auxiliary cavity mode via nonreciprocal coupling.We study the entanglement between the mechanical oscillator and the cavity modes when the two cavities are reciprocally or non-reciprocally coupled.The logarithmic negativity E_(n)^((1))(E_(n)^((2)))is adopted to describe the entanglement degree between the mechanical mode and the optomechanical cavity mode(the auxiliary cavity mode).We find that both E_(n)^((1))and E_(n)^((2))have maximum values in the case of reciprocal coupling.By using nonreciprocal coupling,E_(n)^((1))and E_(n)^((2))can exceed those maximum values,and a wider detuning region where the entanglement exists can be obtained.Moreover,the entanglement robustness with respect to the environment temperature is also effectively enhanced.
