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SummaryWhat is already known about this topic? A passenger who was from the United States was taken to the hotel for the required isolation on November 13, 2020. During the quarantine she was diagnosed as the COVID-19 patient on November 15, 2020. Controlling the importation of COVID-19 remains a major challenge.What is added by this report? In this study, an epidemiological investigation was conducted for a confirmed case of COVID-19, including the treatment records in the hospital and 14-day travel trajectory before the onset of disease.What are the implications for public health practice? This study described an epidemiological investigation and management process on an imported case of COVID-19 and analyzed the test results, aiming to provide useful warnings to strengthen the capacity of public health system in response to the importation.

Phyllostachys praecox is a favorable bamboo species for the production of edible shoots,and has been widely planted in southern China.Intensive management practices such as regular high rate of fertilization and annual heavy winter mulch in the stands established more than 5 years,has been employed by many bamboo growers to improve yields.However,these practices may have adverse effects on the ecosystem.Ammonia-oxidizing archaea(AOA) has been found in various habitats and played a key role in soil nitrification.There is no published information available on the impact of long-term intensive land management practices on the population size and community structure of soil AOA in Phyllostachys praecox stands.In this study,the abundance and composition of soil AOA communities across a long-term chronosequence under intensive managed Phyllostachys praecox stands were investigated using real-time polymerase chain reaction(PCR),denaturing gradient gel electrophoresis(DGGE),cloning and sequencing approaches based on amoA genes.Canonical correspondence analysis(CCA) was also used to determine the environmental variables which are significantly correlated with community structure. Treatments in this study were based on the cultivation history which corresponded to 4,7,9,11 and 15 years after establishment of bamboo stands.Paddy fields with similar topography were used as the control.Each cultivation history had three replications.The archaeal amoA gene copy numbers ranged from 1.79×107 to 3.93×107 per gram of dry soil,and changed greatly in response to the long-term intensive management.The 4-year-old treatment had the highest copy numbers of amoA genes,whereas the lowest copy numbers were recorded in the 9-year-old treatment.Ammonia-oxidizing archaea were more abundant than ammonia-oxidizing bacteria(AOB) in all the corresponding treatments though they were of the same order of magnitude.There was no significant correlation between AOA abundance and soil nitrification potential.The DGGE patterns revealed that the intensive management resulted in an obvious change of the AOA community,significant change was also observed among the treatments with different intensive management history.Phylogenetic analysis of the amoA gene fragments showed that all AOA sequences from different treatments were associated with uncultured Crenarchaeote.The AOA species that adapt to low pH soils dominated in the 7-,9-,11-and 15-year-old treatments while species associated with paddy soil and sediment soil clone dominated in the control and 4-year-old treatment,indicating a pronounced difference in the community composition of AOA in response to the long-term intensive management.Canonical correspondence analysis exhibited a significant difference in microbial community structures between the treatments before and after intensive management application.The 11-and 15-year-old treatments were clustered together,and clearly separated from the 7-and 9-year-old treatments along both the first and second ordination axes.Concentrations of soil NO-3-N,NH+4-N and available phosphorus,and soil pH together explained 62.2% of the total variation of soil AOA community.The first ordination axis explained 33.9% of the variation and the second axis explained 25.8% of the variation.Among the four soil parameters measured,soil NO-3-N concentration explained most of the variation of AOA community,but the influence was not significant(P0.05).The results suggest that long-term intensive management had a significant impact on AOA abundance and composition,and the soil acidification and nutrient accumulation should be important factors influencing the shift of AOA community in the intensively managed P.praecox stands.

Three field experiments at three sites in east Zhejiang Province were conducted to determine the influence of applications of boron (B) on growth, yield, and quality of the red bayberry trees (Myrica rubra Sieb. et Zuca) with a manure species of “Buqizhong” in Linhai city. Ground B application or foliar B spraying significantly improved length and incidence rates of spring and summer shoots and increased fruit set rates, which resulted in the increases in fruit yield (13.7–17.5% for ground B application or 13.2–27.3% for foliar B spraying) and in improvement of fruit quality. The optimum yields were recorded with the treatments of ground B application of 40 g tree−1 of borax or foliar B spraying of 2.0 g L−1 of borax. Spring shoot incidents for the treatment of ground application of 50 g borax tree−1 every year during the experiment (4B50) were significantly higher than that for the treatment of ground application of 50 g borax tree−1 only in the first year of the experiment (B50), but the yield ...