Calling,texting, and searching for information while riding a motorcycle: A study of university students in Vietnam

Objective: The objective of this study was to investigate the prevalence of calling, texting, and searching for information while riding a motorcycle among university students and the influences of sociodemographic characteristics, social norms, and risk perceptions on these behaviors.

Methods: Students at 2 university campuses in Hanoi and Ho Chi Minh City, the 2 largest cities in Vietnam, were invited to participate in an anonymous online survey. Data collection was conducted during March and May 2016.

Results: There were 741 respondents, of whom nearly 90% of students (665) were motorcycle riders. Overall prevalence of mobile phone use while riding is 80.9% (95% confidence interval [CI], 77.9–83.9%) with calling having a higher level of prevalence than texting or searching for information while riding: 74% (95% CI, 70.7–77.3%) vs. 51.7% (95% CI, 47.9–55.5%) and 49.9% (95% CI, 46.1–53.7%), respectively. Random parameter ordered probit modeling results indicate that mobile phone use while riding is associated with gender, motorcycle license duration, perceived crash risk, perceived risk of mobile phone snatching, and perceptions of friends' mobile phone use while riding.

Conclusions: Mobile phone use while riding a motorcycle is highly prevalent among university students. Educational programs should focus on the crash and economic risk of all types of mobile phone use while riding, including calling, texting, and searching for information. In addition, they should consider targeting the influence of social norms and peers on mobile phone use while riding.     

聚甲醛废水的生物强化处理及微生物种群动态分析

聚甲醛工业废水含有甲醛、三聚甲醛和酚类等有害物,而且盐分和COD也较高,很难实现生物处理至达标排放.在聚甲醛污水厂建立中试系统并接种活性污泥,同时投加了经筛选的三聚甲醛降解菌Bacillus methylotrophicus和甲醛降解菌Candida maltosa、Pseudomonsa putida组成的复合菌剂,进行了聚甲醛、甲醛等有毒物质的选择性生物强化,通过温度梯度凝胶电泳(PCR-TGGE)技术对污水反应器进行了微生物群落结构分析,并与污水厂同期出水进行对照研究.结果表明,在投加复合菌剂的强化生物系统中,最终出水的甲醛、三聚甲醛(Trioxane,TOX)和COD降解率分别在97.8%、94.2%和92.6%以上,且系统表现出更高稳定性和抗冲击负荷能力.PCR-TGGE图谱表明,非生物强化系统中未检测到B.methylotrophicus,而该菌在生物强化系统中的活性一直得以维持,其对有毒物质的持续降解解除了其它微生物群落的抑制因子,污泥活性有效增强,说明该菌及复合菌剂确实对TOX及甲醛等毒性物质可有效降解,选择性生物强化可成为工业污水处理的可靠手段之一.     

Normal fetal growth in women with antiphospholipid syndrome treated with high-dose intravenous immunoglobulin (IVIG)

Antiphospholid antibodies are associated with fetal distress and fetal death. Although different therapeutic regimens have been used, the incidence of fetal growth retardation varies between 30 and 60 per cent of reported cases. We report the evolution of fetal growth in patients with antiphospholipid antibody syndrome treated with high-dose intravenous immunoglobulins (IVIG). Fourteen patients with a history of recurrent spontaneous abortion and immunological diagnosis of antiphospholipid syndrome were followed longitudinally. Intravenous immunoglobulin at a dose of 0.5 g/kg body weight for two consecutive days was started from the fifth week of pregnancy and repeated every 4 weeks until the 33rd week of gestation. Fetal biometry was evaluated longitudinally from the appearance of the gestational sac at 4 weekly intervals. In the period between 26 and 34 weeks, the frequency of evaluation was increased to every 14 days. Data obtained were compared with a control group of 70 fetuses with uneventful pregnancies matched for gestational age. Neonatal weight is shown in relation to the centiles for the normal population. One patient out of 14 (7.1 per cent) developed gestational hypertension and abruptio placentae. No other pregnancy complications were seen. No proteinuria was found. The mean maternal age was 31.2±3.8 years. Median birth weight was 3433 g±287. The median centile of the birth weight was 65.3±18.6. Mean gestational age at delivery was 1.3 weeks. No fetal or neonatal growth retardation was seen. No significant differences were found in the biometrical parameters investigated in the various gestational ages vs. the control group (Student's t-test not significant); a significant increase in head circumference (P< 0.001) and abdominal circumference (P< 0.05) was found at 36–37 weeks gestational age in the IVIG-treated fetuses. The presence of antiphospholipid antibodies is considered detrimental for pregnancy outcome because of their negative effects on placental vascular perfusion and fetal transfer of metabolites. The use of IVIG seems to avoid or inhibit the reduced availability of nutrients for the fetal anabolic functions, as the expected reduction in fetal growth was not seen in our series.     

上海市微小颗粒物污染现状调查与分析

对上海市PM2.5的污染现状进行了调查与分析，在2000～2001年间对上海市7个采样点的PM2.5进行了样品采集，初步得到了上海市PM2.5浓度的时间变化规律。全市7个监测点的PM2.5年平均浓度值为60．1μg／m^3，其中市区6个监测点PM2.5的年平均浓度位为65．2μg／m^3，清洁对照点南汇监测点PM2.5的年平均浓度值为41．3μg／m^3；市区冬季的PM2.5月平均浓度值最高，达到80．2μg／m^3,夏季的PM2．5月平均浓度值最低，为35．9μg／m^3，春季和秋季的月平均浓度值分别为72．6μg／m^3，70．4μg／m^3。上海的年平均PM2.5浓度值与美国的标准值(15μg／m^3)相比，超标情况是相当严重的。     

造纸黑液固化技术及有机复合肥肥效试验研究

研究包括两项发明：黑液固化工艺和黑液固化物生产有机NPK复合肥。黑液固化采用交联技术，在常温常压下，向黑液中投加一定量的胶凝剂和交联剂，经搅拌、使黑液在短时间内由液变为固态；通过对固化物成份的分析，以黑液固化物为原料生产有机NPK复合肥，并与一般NPK复混肥进行水稻、花生的肥效对比试验，得出了以黑液固化物生产的有机NPK复合肥肥效优于一般NPK复混肥的结论。     

Applicability of DNA isolated from syncytiotrophoblast vesicles to gene amplification and molecular analysis

Maternal contamination of fetal DNA represents a major problem when highly sensitive molecular techniques are used in the prenatal diagnosis of genetic diseases. For this reason, we have studied the possibility of using DNA isolated from syncytiotrophoblast vesicles as a target of gene amplification (PCR). Three PCR systems were selected which included a repetitive 149 bp fragment of the Y chromosome, the VNTR locus D1S80, and a portion of the β-globin gene. The results of these experiments indicate that DNA isolated from syncytiotrophoblast vesicles is free of maternal contamination and is suitable for gene amplification and DNA analysis.     

The effects of biotic and abiotic factors on the spatial heterogeneity of alpine grassland vegetation at a small scale on the Qinghai–Tibet Plateau (QTP), China

Understanding the complex effects of biotic and abiotic factors on the composition of vegetation is very important for developing and implementing strategies for promoting sustainable grassland development. The vegetation–disturbance–environment relationship was examined in degraded alpine grasslands in the headwater areas of three rivers on the Qinghai–Tibet Plateau in this study. The investigated hypotheses were that (1) the heterogeneity of the vegetation of the alpine grassland is due to a combination of biotic and abiotic factors and that (2) at a small scale, biotic factors are more important for the distribution of alpine vegetation. On this basis, four transects were set along altitudinal gradients from 3,770 to 3,890 m on a sunny slope, and four parallel transects were set along altitudinal gradients on a shady slope in alpine grasslands in Guoluo Prefecture of Qinghai Province, China. It was found that biological disturbances were the major forces driving the spatial heterogeneity of the alpine grassland vegetation and abiotic factors were of secondary importance. Heavy grazing and intensive rat activity resulted in increases in unpalatable and poisonous weeds and decreased fine forages in the form of sedges, forbs, and grasses in the vegetation composition. Habitat degradation associated with biological disturbances significantly affected the spatial variation of the alpine grassland vegetation, i.e., more pioneer plants of poisonous or unpalatable weed species, such as Ligularia virgaurea and Euphorbia fischeriana, were found in bare patches. Environmental/abiotic factors were less important than biological disturbances in affecting the spatial distribution of the alpine grassland vegetation at a small scale. It was concluded that rat control and light grazing should be applied first in implementing restoration strategies. The primary vegetation in lightly grazed and less rat-damaged sites should be regarded as a reference for devising vegetation restoration measures in alpine pastoral regions.