Based on a combination of morphology and molecular data of ribosomal DNA genes,a new diatom genus Lineaperpetua gen.nov.Yu,You,Kociolek&Wang is described.The features that help define Lineaperpetua at the level of...Based on a combination of morphology and molecular data of ribosomal DNA genes,a new diatom genus Lineaperpetua gen.nov.Yu,You,Kociolek&Wang is described.The features that help define Lineaperpetua at the level of genus include:a tangentially undulated valve face;continuous cribra areolae on the valve interior consisting of pores arranged as strips;single rimoportula located inside the ring of marginal fultoportulae.Additionally,phylogenetic analysis based on nuclear small subunit(SSU)rDNA sequences and nuclear large subunit(LSU)rDNA gene placed the three strains of L.lacustris in a single,monophyletic clade at a considerable sequence distance from the other genera(Thalassiosira,Conticribra,Planktoniella,Shinodiscus,and other genera)belonging to Thalassiosirales.Despite the similarities with some species of Thalassiosira,Conticribra,and Spicaticribra,the suite of features found in Lineaperpetua differentiate it from these other genera.These molecular data and morphological characters suggest an affinity of the new genus to the Thalassiosiraceae.展开更多
Panax ginseng C.A.Mey.is an important plant species used in traditional Chinese medicine,whose primary active ingredient is a ginsenoside.Ginsenoside biosynthesis is not only regulated by transcription factors but als...Panax ginseng C.A.Mey.is an important plant species used in traditional Chinese medicine,whose primary active ingredient is a ginsenoside.Ginsenoside biosynthesis is not only regulated by transcription factors but also controlled by a variety of structural genes.Nonetheless,the molecular mechanism underlying ginsenoside biosynthesis has always been a topic in the discussion of ginseng secondary metabolites.Squalene epoxidase(SQE)is a key enzyme in the mevalonic acid pathway,which affects the biosynthesis of secondary metabolites such as terpenoid.Using ginseng transcriptome,expression,and ginsenoside content databases,this study employed bioinformatic methods to systematically analyze the genes encoding SQE in ginseng.We first selected six PgSQE candidates that were closely involved in ginsenoside biosynthesis and then identified PgSQE08-01 to be highly associated with ginsenoside biosynthesis.Next,we constructed the overexpression vector pCAMBIA3301-PgSQE08-01 and the RNAi vector pART27-PgSQE08-01 and transformed ginseng adventitious roots using Agrobacterium rhizogenes,to obtain positive hairy-root clones.Thereafter,quantitative reverse transcriptionpolymerase chain reaction and high-performance liquid chromatography were used to determine the expression of relevant genes and ginsenoside content,respectively.Then,we focused on the function of PgSQE08-01 gene,which was noted to be involved in ginsenoside biosynthesis.Thus,these findings not only provided a molecular basis for the identification of important functional genes in ginseng but also enriched genetic resources for the biosynthesis of ginsenosides using synthetic biology.展开更多
We propose an eye-shaped keyboard for high-speed text entry in virtual reality (VR), having the shape of dual eyes with characters arranged along the curved eyelids, which ensures low density and short spacing of the ...We propose an eye-shaped keyboard for high-speed text entry in virtual reality (VR), having the shape of dual eyes with characters arranged along the curved eyelids, which ensures low density and short spacing of the keys. The eye-shaped keyboard references the QWERTY key sequence, allowing the users to benefit from their experience using the QWERTY keyboard. The user interacts with an eye-shaped keyboard using rays controlled with both the hands. A character can be entered in one step by moving the rays from the inner eye regions to regions of the characters. A high-speed auto-complete system was designed for the eye-shaped keyboard. We conducted a pilot study to determine the optimal parameters, and a user study to compare our eye-shaped keyboard with the QWERTY and circular keyboards. For beginners, the eye-shaped keyboard performed significantly more efficiently and accurately with less task load and hand movement than the circular keyboard. Compared with the QWERTY keyboard, the eye-shaped keyboard is more accurate and significantly reduces hand translation while maintaining similar efficiency. Finally, to evaluate the potential of eye-shaped keyboards, we conducted another user study. In this study, the participants were asked to type continuously for three days using the proposed eye-shaped keyboard, with two sessions per day. In each session, participants were asked to type for 20min, and then their typing performance was tested. The eye-shaped keyboard was proven to be efficient and promising, with an average speed of 19.89 words per minute (WPM) and mean uncorrected error rate of 1.939%. The maximum speed reached 24.97 WPM after six sessions and continued to increase.展开更多
基金the Postdoctoral Science Foundation of China(No.2021 M 703434)the National Natural Science Foundation of China(Nos.32100165,32170205)the Natural Science Foundation of Shanghai(No.21 ZR 144730)。
文摘Based on a combination of morphology and molecular data of ribosomal DNA genes,a new diatom genus Lineaperpetua gen.nov.Yu,You,Kociolek&Wang is described.The features that help define Lineaperpetua at the level of genus include:a tangentially undulated valve face;continuous cribra areolae on the valve interior consisting of pores arranged as strips;single rimoportula located inside the ring of marginal fultoportulae.Additionally,phylogenetic analysis based on nuclear small subunit(SSU)rDNA sequences and nuclear large subunit(LSU)rDNA gene placed the three strains of L.lacustris in a single,monophyletic clade at a considerable sequence distance from the other genera(Thalassiosira,Conticribra,Planktoniella,Shinodiscus,and other genera)belonging to Thalassiosirales.Despite the similarities with some species of Thalassiosira,Conticribra,and Spicaticribra,the suite of features found in Lineaperpetua differentiate it from these other genera.These molecular data and morphological characters suggest an affinity of the new genus to the Thalassiosiraceae.
基金This work was supported by an award from the Department of Science and Technology of Jilin Province(20210402043GH and 20210204063YY).
文摘Panax ginseng C.A.Mey.is an important plant species used in traditional Chinese medicine,whose primary active ingredient is a ginsenoside.Ginsenoside biosynthesis is not only regulated by transcription factors but also controlled by a variety of structural genes.Nonetheless,the molecular mechanism underlying ginsenoside biosynthesis has always been a topic in the discussion of ginseng secondary metabolites.Squalene epoxidase(SQE)is a key enzyme in the mevalonic acid pathway,which affects the biosynthesis of secondary metabolites such as terpenoid.Using ginseng transcriptome,expression,and ginsenoside content databases,this study employed bioinformatic methods to systematically analyze the genes encoding SQE in ginseng.We first selected six PgSQE candidates that were closely involved in ginsenoside biosynthesis and then identified PgSQE08-01 to be highly associated with ginsenoside biosynthesis.Next,we constructed the overexpression vector pCAMBIA3301-PgSQE08-01 and the RNAi vector pART27-PgSQE08-01 and transformed ginseng adventitious roots using Agrobacterium rhizogenes,to obtain positive hairy-root clones.Thereafter,quantitative reverse transcriptionpolymerase chain reaction and high-performance liquid chromatography were used to determine the expression of relevant genes and ginsenoside content,respectively.Then,we focused on the function of PgSQE08-01 gene,which was noted to be involved in ginsenoside biosynthesis.Thus,these findings not only provided a molecular basis for the identification of important functional genes in ginseng but also enriched genetic resources for the biosynthesis of ginsenosides using synthetic biology.
文摘We propose an eye-shaped keyboard for high-speed text entry in virtual reality (VR), having the shape of dual eyes with characters arranged along the curved eyelids, which ensures low density and short spacing of the keys. The eye-shaped keyboard references the QWERTY key sequence, allowing the users to benefit from their experience using the QWERTY keyboard. The user interacts with an eye-shaped keyboard using rays controlled with both the hands. A character can be entered in one step by moving the rays from the inner eye regions to regions of the characters. A high-speed auto-complete system was designed for the eye-shaped keyboard. We conducted a pilot study to determine the optimal parameters, and a user study to compare our eye-shaped keyboard with the QWERTY and circular keyboards. For beginners, the eye-shaped keyboard performed significantly more efficiently and accurately with less task load and hand movement than the circular keyboard. Compared with the QWERTY keyboard, the eye-shaped keyboard is more accurate and significantly reduces hand translation while maintaining similar efficiency. Finally, to evaluate the potential of eye-shaped keyboards, we conducted another user study. In this study, the participants were asked to type continuously for three days using the proposed eye-shaped keyboard, with two sessions per day. In each session, participants were asked to type for 20min, and then their typing performance was tested. The eye-shaped keyboard was proven to be efficient and promising, with an average speed of 19.89 words per minute (WPM) and mean uncorrected error rate of 1.939%. The maximum speed reached 24.97 WPM after six sessions and continued to increase.