Retrieving chlorophyll content and equivalent water thickness of Moso bamboo(Phyllostachys pubescens) forests under Pantana phyllostachysae Chao-induced stress from Sentinel-2A/B images in a multiple LUTs-based PROSAIL framework

Biochemical components of Moso bamboo(Phyllostachys pubescens)are critical to physiological and ecological processes and play an important role in the material and energy cycles of the ecosystem.The coupled PROSPECT with SAIL(PROSAIL)radiative transfer model is widely used for vegetation biochemical component content inversion.However,the presence of leaf-eating pests,such as Pantana phyllostachysae Chao(PPC),weakens the performance of the model for estimating biochemical components of Moso bamboo and thus must be considered.Therefore,this study considered pest-induced stress signals associated with Sentinel-2A/B images and field data and established multiple sets of biochemical canopy reflectance look-up tables(LUTs)based on the PROSAIL framework by setting different parameter ranges according to infestation levels.Quantitative inversions of leaf area index(LAI),leaf chlorophyll content(LCC),and leaf equivalent water thickness(LEWT)were derived.The scale conversions from LCC to canopy chlorophyll content(CCC)and LEWT to canopy equivalent water thickness(CEWT)were calculated.The results showed that LAI,CCC,and CEWT were inversely related with PPC-induced stress.When applying multiple LUTs,the p-values were<0.01;the R2 values for LAI,CCC,and CEWT were 0.71,0.68,and 0.65 with root mean square error(RMSE)(normalized RMSE,NRMSE)values of 0.38(0.16),17.56μg cm-2(0.20),and 0.02 cm(0.51),respectively.Compared to the values obtained for the traditional PROSAIL model,for October,R2 values increased by 0.05 and 0.10 and NRMSE decreased by 0.09 and 0.02 for CCC and CEWT,respectively and RMSE decreased by 0.35μg cm-2 for CCC.The feasibility of the inverse strategy for integrating pest-induced stress factors into the PROSAIL model,while establishing multiple LUTs under different pest-induced damage levels,was successfully demonstrated and can potentially enhance future vegetation parameter inversion and monitoring of bamboo forest health and ecosystems.

加强创新能力培养,推进高等医学教育改革

创新在社会被越来越多的人所关注,是一个国家和民族持续发展的源泉和动力。同时大学生作为未来的社会人才主体,肩负着实现中华民族伟大复兴的重要历史使命,医学生培养在社会更是有着举足轻重的地位。调整高等教育观念,强化教育教学改革,努力培养和提高医学生的创新能力显得至关重要。本文从整合课程体系、创新教学方法,翻转第一课堂、拓展教育载体,加强第二课堂等方面对提高医学生的创新能力提出策略和建议。

Genetic Diversity of Lotus(Nelumbo nucifera Gaertn.) Cultivars Revealed by ISSR Analysis

[ Objectives ] This study was conducted to investigate the genetic diversity of 20 lotus （Nelumbo nucifera Gaertn） samples. [ Methods ] On this optimal ISSR amplification system, 16 primers were screened with good polymorphism, and the DNA was used to amplify the 20 plant samples. [ R^ults] The 16 primers produced 225 loci, of which 170 were polymorphic, and the polymorphic loci percentage was up to 75.56%. The genetic similarity coefficients between the 20 vari- eties ranged from 0. 577 8 to 0.951 1, which were calculated by POPGENE32. The 20 varieties by UPMGA analysis could be clustered into 2 groups, the first of which included Baiyangdian red lotus and Donggua lotus, and other varieties was included in the second group. [ Conchmions] ISSR molecular markers could be effectively used in genetic diversity and fingerprint analysis for different lotus varieties.

Allele-aware chromosome-scale assembly of the allopolyploid genome of hexaploid Ma bamboo(Dendrocalamus latiflorus Munro)

Dendrocalamus latiflorus Munro is a woody clumping bamboo with rapid shoot growth.Both genetic transformation and clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)gene editing techniques are available for D.latiflorus,enabling reverse genetic approaches.Thus,D.latiflorus has the potential to be a model bamboo species.However,the genome sequence of D.latiflorus has remained unreported due to its polyploidy and large genome size.Here,we sequenced the D.latiflorus genome and assembled it into three allele-aware subgenomes(AABBCC),representingthe largest genome of a major bamboo species.We assembled 70 allelic chromosomes(2,737 Mb)for hexaploid D.latiflorus using both singlemolecule sequencing from the Pacific Biosciences(Pac Bio)Sequel platform and chromosome conformation capture sequencing(Hi-C).Repetitive sequences comprised 52.65%of the D.latiflorus genome.We annotated 135231 protein-coding genes in the genome based on transcriptomes from eight different tissues.Transcriptome sequencing using RNA-Seq and Pac Bio singlemolecule real-time long-read isoform sequencing revealed highly differential alternative splicing(AS)between non-abortive and abortive shoots,suggesting that AS regulates the abortion rate of bamboo shoots.This high-quality hexaploid genome and comprehensive strand-specific transcriptome datasets for this Poaceae family member will pave the way for bamboo research using D.latiflorus as a model species.

Development of a fluorescent probe hydrolysis-insulated isothermal PCR for rapid and sensitive on-site detection of African swine fever virus

Dear Editor,African swine fever virus(ASFV),the sole member of the family Asfarviridae,is the causative agent of African swine fever(ASF),a viral disease that leads to high mortality in domestic pigs.Since firstly identified in Kenya in the 1920s,ASFV has been prevalent in Africa,Europe,and Russian Federation(Sanchez et al.,2019).Recently,ASFV was introduced to Asian countries including China,Mongolia,Vietnam,Cambodia,Laos and South Korea,which lead to huge economic losses to local pig industries(Li and Tian,2018;Gaudreault and Richt,2019).The first case of ASFV in China was reported in August 2018(Zhou et al.,2018).