Chinese wingnut(Pterocarya stenoptera)is a medicinally and economically important tree species within the family Juglandaceae.However,the lack of high-quality reference genome has hindered its in-depth research.In thi...Chinese wingnut(Pterocarya stenoptera)is a medicinally and economically important tree species within the family Juglandaceae.However,the lack of high-quality reference genome has hindered its in-depth research.In this study,we successfully assembled its chromosome-level genome and performed multiomics analyses to address its evolutionary history and synthesis of medicinal components.A thorough examination of genomes has uncovered a significant expansion in the Lateral Organ Boundaries Domain gene family among the winged group in Juglandaceae.This notable increase may be attributed to their frequent exposure to flood-prone environments.After further differentiation between Chinese wingnut and Cyclocarya paliurus,significant positive selection occurred on the genes of NADH dehydrogenase related to mitochondrial aerobic respiration in Chinese wingnut,enhancing its ability to cope with waterlogging stress.Comparative genomic analysis revealed Chinese wingnut evolved more unique genes related to arginine synthesis,potentially endowing it with a higher capacity to purify nutrient-rich water bodies.Expansion of terpene synthase families enables the production of increased quantities of terpenoid volatiles,potentially serving as an evolved defense mechanism against herbivorous insects.Through combined transcriptomic and metabolomic analysis,we identified the candidate genes involved in the synthesis of terpenoid volatiles.Our study offers essential genetic resources for Chinese wingnut,unveiling its evolutionary history and identifying key genes linked to the production of terpenoid volatiles.展开更多
The friction behaviors of steel sheets at the corners of die and punch, under different conditions of surface textures (laser beam texture, shot blast texture), steel sheet rolling directions and lubricants, are studi...The friction behaviors of steel sheets at the corners of die and punch, under different conditions of surface textures (laser beam texture, shot blast texture), steel sheet rolling directions and lubricants, are studied by both SEM micro surface observations and friction coefficients measurement. The results show the friction coefficient at the corner of die is smaller than that at the corner of punch during stamping. The friction coefficient along rolling direction is lower than that along transverse direction, especially at the corner of punch. Differential initial surface texture has different sensitivity of friction coefficient to the lubricants. The sheet surface with laser beam texture (LBT) has shown a stronger adaptation to various lubricants than that with shot blast texture (SBT). After stamping, the surface with laser beam texture is still clear, the shot blast texture is indistinct.展开更多
基金supported by National Natural Science Foundation of China(32360307)the Natural Science Foundation of Inner Mongolia(2023MS03031)+1 种基金Inner Mongolia Grassland Talents Project(3211002406)the Open Fund of State Key Laboratory of Tree Genetics and Breeding(Chinese Academy of Forestry)(Grant No.TGB2021004).
文摘Chinese wingnut(Pterocarya stenoptera)is a medicinally and economically important tree species within the family Juglandaceae.However,the lack of high-quality reference genome has hindered its in-depth research.In this study,we successfully assembled its chromosome-level genome and performed multiomics analyses to address its evolutionary history and synthesis of medicinal components.A thorough examination of genomes has uncovered a significant expansion in the Lateral Organ Boundaries Domain gene family among the winged group in Juglandaceae.This notable increase may be attributed to their frequent exposure to flood-prone environments.After further differentiation between Chinese wingnut and Cyclocarya paliurus,significant positive selection occurred on the genes of NADH dehydrogenase related to mitochondrial aerobic respiration in Chinese wingnut,enhancing its ability to cope with waterlogging stress.Comparative genomic analysis revealed Chinese wingnut evolved more unique genes related to arginine synthesis,potentially endowing it with a higher capacity to purify nutrient-rich water bodies.Expansion of terpene synthase families enables the production of increased quantities of terpenoid volatiles,potentially serving as an evolved defense mechanism against herbivorous insects.Through combined transcriptomic and metabolomic analysis,we identified the candidate genes involved in the synthesis of terpenoid volatiles.Our study offers essential genetic resources for Chinese wingnut,unveiling its evolutionary history and identifying key genes linked to the production of terpenoid volatiles.
文摘The friction behaviors of steel sheets at the corners of die and punch, under different conditions of surface textures (laser beam texture, shot blast texture), steel sheet rolling directions and lubricants, are studied by both SEM micro surface observations and friction coefficients measurement. The results show the friction coefficient at the corner of die is smaller than that at the corner of punch during stamping. The friction coefficient along rolling direction is lower than that along transverse direction, especially at the corner of punch. Differential initial surface texture has different sensitivity of friction coefficient to the lubricants. The sheet surface with laser beam texture (LBT) has shown a stronger adaptation to various lubricants than that with shot blast texture (SBT). After stamping, the surface with laser beam texture is still clear, the shot blast texture is indistinct.