综合预防措施对控制口腔固定矫治中牙釉质脱矿的效果分析

随着口腔固定矫治器在临床上的广泛应用,其造成牙釉质脱矿的现象受到了大家的关注,如果不采取必要的防护措施,可导致牙齿龋坏、牙髓炎等不良后果。本文通过对正畸矫治中的患者采用不同的预防措施,观察其牙釉质脱矿的发生情况,旨在寻找一种有效而简单易行的预防固定矫治中牙釉质脱矿的方法,现报告如下。

三种氧浓度气调下清香型烟叶化学成分的变化

选择3种清香型产地复烤烟叶,分别用2%以下氧浓度、6%~8%氧浓度和21%氧浓度气调养护醇化,分析烟叶采用3种气调方式醇化时化学成分的含量变化差异。结果表明,随着醇化进行,总植物碱含量变化较小,pH、多酚含量、氨基酸含量呈下降趋势,两糖比逐步上升;3种气调方式中,pH下降幅度、多酚消耗率和氨基酸消耗率均表现为21%氧浓度>6%~8%氧浓度>2%以下氧浓度,21%氧浓度气调的化学成分变化波动最大,2%以下氧浓度气调波动相对平缓;在高温季节,pH变幅、多酚消耗率、氨基酸消耗率都有一个加速变化的过程;3种清香型烟叶因为产地不同,常规化学成分差异较大,云南普洱B1F(A)烟叶、四川西昌B1F烟叶的pH、多酚含量和氨基酸含量明显大于福建龙岩B1F(A)烟叶。

Preliminary studies on the dynamic prediction method of rainfall-triggered landslide

Rainfall-triggered landslides have posed significant threats to human lives and property each year in China. This paper proposed a meteorologicalgeotechnical early warning system GRAPES-LFM(GRAPES: Global and Regional Assimilation and Pr Ediction System; LFM: Landslide Forecast Model),basing on the GRAPES model and the landslide predicting model TRIGRS(Transient Rainfall Infiltration and Grid-based Regional Slope-Stability Model) for predicting rainfall-triggered landslides.This integrated system is evaluated in Dehua County,Fujian Province, where typhoon Bilis triggered widespread landslides in July 2006. The GRAPES model runs in 5 km×5 km horizontal resolution, and the initial fields and lateral boundaries are provided by NCEP(National Centers for Environmental Prediction) FNL(Final) Operational Global Analysis data. Quantitative precipitation forecasting products of the GRAPES model are downscaled to 25 m×25 m horizontal resolution by bilinear interpolation to drive the TRIGRS model. Results show that the observed areas locate in the high risk areas, and the GRAPES-LFM model could capture about 74% of the historical landslides with the rainfall intense 30mm/h. Meanwhile, this paper illustrates the relationship between the factor of safety(FS) and different rainfall patterns. GRAPES-LFM model enables us to further develop a regional, early warning dynamic prediction tool of rainfall-induced landslides.

海口市秀英区按蚊种类、分布及季节消长调查

目的了解海口市秀英区2018年按蚊种类、分布及季节消长情况,为评估疟疾传播风险,制订消除疟疾后的防控策略和方案提供科学依据。方法采用灯光诱捕法(诱蚊灯法)、动物诱捕法(动物帐诱法)、人诱捕法(人诱停落法),在秀英区6个乡镇中每个乡镇随机抽取1个自然村进行按蚊种类及分布调查;选取1个自然村为监测点,研究媒介按蚊季节消长规律。结果6个调查点共捕获按蚊6种458只,其中中华按蚊218只(47.60%),棋斑按蚊187只(40.83%),迷走按蚊44只(9.61%),乌头按蚊4只(0.87%),须喙按蚊3只(0.66%)、带足按蚊2只(0.44%)。季度消长监测点1—12月共捕获按蚊7种1421只。其中中华按蚊、棋斑按蚊、迷走按蚊所占比例分别为44.76%、39.55%、15.20%。按蚊数量从4月份开始增多,9月达到高峰,5—11月捕获数占全年89.23%;中华按蚊全年都有活动。结论2018年海口市秀英区主要按蚊种类为中华按蚊、棋斑按蚊和迷走按蚊,未发现以往的主要传疟媒介微小按蚊。按蚊密度在2018年5—11月有一持续高峰,其他月份密度均处于较低水平。